You have skipping or other problems with your stereo Bluetooth headphones? Read this!

You have skipping or other problems with your stereo Bluetooth headphones? Read this! - General Topics

Unfortunately, there are major incompatibility problems with current Pocket PC models and stereo Bluetooth headphones – to the point of being completely useless.
For example, I’m unable to use my – otherwise excellent - Plantronics Pulsar 590A with the built-in A2DP (that is, stereo headphone) support of my Dell Axim x51v and HTC Universal (both having AKU2+ ROM’s; that is, their built-in Microsoft Bluetooth stack already supports A2DP). Some 200-400 milliseconds after starting to play anything (there is no such problem with system sounds – clicks and so on), the headphone just goes quiet, and the sound will only return after 5-10 seconds. To get lost again, of course, if I (re)start playing anything in any media player.
Fortunately, I have no such problems with my WM5-upgraded (2.01) HP iPAQ hx4700, the Dell Axim x51v with the Widcomm hack, the iPAQ 2210, HTC Wizard and Fujitsu-Siemens Pocket Loox 720 (the latter three with various hacks and other, smaller problems; the first two has no real problems, the x51v with the Flow hack).
People with other headphone models have wildly different problems. Most of them is the “skipping” problem – the sound just stops for some hundred milliseconds or some parts of the sound stream is just ignored.
In this article, (in addition to my already-published, Widcomm-only global bitstream speed setting (BTSpeedSwitcher) and FlowControl article) I elaborate on how the two A2DP implementations (Widcomm, Microsoft (MS)) can be fine-tuned to make your headphones work.
1.1 Communication speed
Most skipping or quieting problems are caused by the too high communication speed between the PDA and the headphones. In these cases, you should first decrease this speed to see whether it helps. If you can get rid of the skips without scarifying much sound quality, then, you can actually make your PDA and headphones compatible.
1.2 Modifying the given values
All the values I’ll elaborate on in this article don’t exist in the Registry by default. This is why I’ve also provided registry import files – you’ll only need to click them from inside Resco Registry Editor (File / Import), the, in my opinion, (for the price) best registry editor for the Pocket PC as can also be seen in the Registry Editor Bible.
These reg. import files contain some default values, which you will most likely need / want to modify with the registry editor (to slightly decrease / increase to decrease the communication speed to get rid of the problems or increase it to have better sound quality, respectively). With most devices (in this test, PL720, hx4700 and x51v with both BT stacks), after you modify a sound quality-related value in the Registry, you’ll only need to restart the BT stack to be able to test the modified value. That is, explicitly stop and restart the BT unit. With the Widcomm BT stack, you’ll need to click “Turn Bluetooth OFF” in the context menu of the BT icon and, then, staright go back to Bluetooth Manager and just reconnect the headphone. With the MS BT stack, in Bluetooth Settings, just untick the “Turn on Bluetooth” checkbox and click OK (or, if it has a Communication Manager dialog like PPC Phone Edition devices, stop BT there); then, re-enable BT and reconnect to the headphones by going back to Bluetooth Settings and selecting “Set as Wireless Stereo” in the context menu of the given stereo headphone.
Note that this (a simple BT stack restart is sufficient) is not the case with the HTC Wizard: with it, for the changes to be registered, you’ll need to power the device completely off by long-pressing the Power button and answering Yes to the question about completely powering down the device. After it is shut down, just press the Power button again and it’ll reboot. It's only then will the changes have effect.
2. Microsoft BT stack: BitPool
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Bluetooth\A2DP\Settings\BitPool
(Registry import script available here)
With the Microsoft BT stack, you can set the BitPool value, which has a direct effect on the communication speed between the PDA and the headset. Unlike with the Widcomm BT stack, in here, you can’t directly supply the number of kilobytes the PDA will transfer the sound to the headphones. Here, you’ll need to multiply the value of this registry entry with 6.5 to get the approximate value of the transfer rate.
To fix most skipping problems, you will want to decrease this value (and you will want to increase it to try to enhance the sound quality).
Unfortunately, decreasing it may result in a horrible sound quality decrease. For example, in my tests, I’ve found out that only with the value 24 can I have uninterrupted music transfer between by Dell Axim x51v (with the original MS stack) and my 590A. With any value over that (even 25), there started to be skips.
Increasing it will not necessarily result in a far better sound quality. On my HTC Wizard ((European) MDA Vario by its origins with the KTamas / bepe AKU3.2 RC1 ROM on it), which has a very bad A2DP sound quality by default, increasing this value to even 120 didn’t help – the very bad “typical for non-filtered contents sampled at a low sampling frequency” distortion remained. That is, you can’t raise the sound quality of the Wizard; not even with extra high BitPool values.
I’ve also played a lot with the MinBitPool Registry value (under the same key; see this forum post), without any success (on my Wizard). That is, at least with the current Wizard hack, it’s pretty futile to try to play with MinBitPool, it seems.
The same stands for SampleRate: it has no effect at all, it seems.
More info here (AGAIN, please note that setting SampleRate, MinBitPool and MaxBitPool don’t have any effect, at least not on the Wizard!)
3. Tweakability of the Widcomm BT stack
Unlike with the MS BT stack (which only has one parameter to be tweaked), there are far more locations / parameters this stack can be tweaked at.
Note that here, I don’t elaborate on the two previous hacks to combat the “transmission stops after a few dozen minutes; otherwise, it's pretty OK” problem – please see the already-linked global bitstream speed setting (BTSpeedSwitcher) and FlowControl article if you have the previously-mentioned problem. The hacks described in this article “only” help with constant skipping problems (and transfer quality fine-tuning), which are completely independent of the subject of my previous article.

3.1 LineSpeed
HKEY_LOCAL_MACHINE\SOFTWARE\Widcomm\Plugin\AV\LineSpeed
(Registry import script available here)
This registry value is very similar to the above-introduced MS BT stack-specific BitPool. The difference is that it allows Widcomm users to directly supply the bit transfer speed between the PDA and the headphones – no multiplication is necessary.
The valid values start with 64 (that is, 64 kbit/s), which results in intolerably bad sound quality. 128 is still very bad; it’s with 192 that the sound quality starts to become acceptable. With 256, it’s already pretty hard to distinguish from the sound quality higher values result in – that is, you’ll want to start with the value 256 (and only slightly decrease to see whether it helps get rid of the problems).
I’ve even tested my Pocket PC’s with extremely high (400-600 kbps) values; they haven’t delivered noticeably (or at all) better sound quality than, say, the 320 kbps setting and they rendered the transmission far more unreliable / unstable, if working at all. For example, even at 400 kbps, my iPAQ hx4700 paused and skipped from time to time; at 600 kbps, it only played for some 20 secs and, then, went quiet. The Pocket Loox 720 fared a bit better at even 460 kbps but, again, the sound quality gain (if any) wasn’t worth the trouble and the additional BT communication load.
Speaking of the PL720, I’ve also tested whether a slightly lower, but still very good transmission speed (256 kbps) completely gets rid of the need for the FlowControl hack (again, see my previous article on the latter). While it played music for more than two hours, around the third hour, it stopped playing. Furthermore, it still had slight pauses (albeit I haven’t noticed playback at a higher pitch in the following 8-10 seconds). That is, you won’t want to completely get rid of the FlowControl hack. (I’ve also tested the PL720 with the FlowControl hack disabled and at 460 kbps – as opposed to the pretty stable 256 kbps. It shuts down itself after 3-4 minutes and, therefore, is useless, as I’ve expected.)
3.2 Blocks and SubBand
HKEY_LOCAL_MACHINE\SOFTWARE\WIDCOMM\Plugin\AV\Blocks
and
HKEY_LOCAL_MACHINE\SOFTWARE\WIDCOMM\Plugin\AV\SubBands
(Registry import script available here)
These two values can also be used to fine-tune your transmission parameters under the Widcomm BT stack. They are settable between 4 and 16. With higher values that 16, the Pocket PC won’t connect to the headphones; with lower values than 4, nothing will be heard (not even system sounds – clicks and the like). The lower the value, the worse the sound quality.
Of the two, the second, ‘SubBands’ parameter has a much less effect on the sound quality as the first (Blocks). For example, if you leave Blocks at (the best) 16 and set SubBands to 4, the sound quality will degrade only slightly (and, with the SubBands value of 8, it’ll be almost impossible to notice any quality difference). It will be in no way as bad as, say, using 128 kbps LineSpeed and will still be much better than the A2DP sound quality of the HTC Wizard.
If, on the other hand, you set Blocks to be 4 and leave SubBands at (the best) 16, the sound quality will be considerably worse. It’ll be, say, as setting the line speed (see section 3.1) to 96 kbps.
That is, first, start play with the SubBands value. Decrease it to, first, 8 and if it doesn’t help, 4. Then, if the latter doesn’t result in any usable result, start decreasing Blocks. Again, descreasing Blocks will have a very bad effect on the sound quality.
Note that Blocks only seems to have effect on 1.7 Widcomm versions; 1.5 versions (like the PDA2k upgrade usable on the Pocket Loox 720) don’t take this value into account at all. (Haven’t tested it with 1.6 like the HP update usable on WM2003 and some WM2003SE devices.)
(These three hacks were originally discovered by the well-known mikespikel in this thread.)
3.3 Other additional registry values available in desktop Widcomm implementations and some forum posts
I’ve also thoroughly tested the desktop Windows values listed here. They allow for tuning the bits-per-sample ("BitsPerSample"), setting the sampling frequency ("SamplesPerSec"; the case is similar to the “SampleRate” case of the MS BT stack) and setting the number of channels (mono or stereo; "Channels"). None of them seems to have any effect. If you still want to give it a try, the registry import script is available here.

Related

TUTORIAL:Everything you need to know about using traditional (mono)Bluetooth headsets

Listen to your Pocket PC on your traditional mono Bluetooth headset and/or use its built-in microphone for PDA-based recording!
(I’ve been constantly receiving questions about all these questions on various Pocket PC boards and newsgroups; now that I’m tired of answering the same question at least five times a day, I’ve decided to dedicate a complete write-up to it.)
I’ve published several articles on A2DP and AVRCP (please see the Bluetooth category in the Smartphone & Pocket PC Magazine Expert Blog), which is a great way to listen to music wirelessly in (almost) Hi-Fi quality and stereo.
The “traditional” headset mode, on the other hand, may be much more useful for much more Pocket PC users because
There are much more cheap, “traditional”, mono Bluetooth headsets than expensive and bulky A2DP stereo headphones. They are available in all phone shops everywhere and are used by, it seems, everywhere. An example of them is the X3 micro, of which Jack Cook has just published an excellent review
To listen to, say, GPS navigation, the (not very good, phone-grade) quality of these headsets may be sufficient
Furthermore, they offer two serious (!) advantages over the A2DP mode, because of which you may want to go for the traditional headset mode instead of the high-quality A2DP mode even if you have a full-blown A2DP stereo headphone:
when you actively connect a headset device to your PDA, you will not only use the PDA-to-headset sound routing, but also the opposite direction. That is, if you, for example, want to use your PDA to record your speech (and that of your environment), and the slightly degraded (recording) sound recording quality (which won’t really be an issue when you only plan to record speech) isn’t an issue, you may want to opt for using your headset to record your speech as opposed to your PDA, which, then, can even be in your pocket or even in your suitcase.
the CPU usage of the “plain” PDA-to- headset unit will be about an order of magnitude less than that of A2DP. For example, on the non-overclocked HTC Wizard, device.exe consumes between 28 and 35% with A2DP, depending on the quality. With simple non-Hi-Fi / non-stereo sound routing, device.exe doesn’t consume anything at all, compared to the default (sound isn’t routed) case. That is, when battery life and / or responsiveness is of paramount importance and the heavy sound quality degradation / lack of stereo, you may want to prefer the low-quality, mono but non-battery-consuming headset mode to high-quality, but heavily battery-consuming mode, which also makes your Pocket PC much less responsive.
Being able to constantly (!) route the sound of your PDA to your mono headset, first, depends on the maker of your built-in Bluetooth stack. In here, Widcomm / Broadcom users (Widcomm is used in most PDA’s with operating systems prior to WM5 except for the Phone Edition models of HTC; as far as WM5 models are concerned, all Acers, HP iPAQs have sticked with this stack; the majority of Fujitsu-Siemens Pocket PC’s (except for the T8x0) and all Dell Axims (which were all Widcomm-based in the pre-WM5 times) have switched to the Microsoft BT stack), as usual, have a lead because they don’t need additional hacks / third-party applications, as opposed to the Microsoft stack.
Widcomm / Broadcom BT stack
The newer Widcomm / Broadcom BT stack versions (starting with BT stack 1.5 built into most Widcomm-based WM2003SE devices; this is also true with 1.6 and the latest 1.7, which is used in current Widcomm-based WM5 Pocket PC’s) all natively support routing the sound to your mono headset (and, of course, vice versa) as can be seen in this and this screenshots. That is, in these devices, just go to Bluetooth Manager / New, switch the headset to discoverable mode and select Hands-free / Headset setup. After creating a shortcut to the connection, just double-click it to connect (or, press the button on your headset / switch it on; then, they may automatically connect. Note that, with some headsets (for example, the Plantronics Pulsar 590A and the Dell Axim x51v with the Widcomm BT hack, the "hacked" (see below) HP iPAQ 2210 or the WM5-upgraded iPAQ hx4700), after connection, you'll need to press the headset button once more, when you hear a ringing sound. It's only then that the sound routing will be started.)
Older Widcomm versions (up to 1.4 built into most pre-WM2003SE Pocket PC’s; for example, the HP iPAQ 2210), however, don’t offer Hands-free / Headset setup in the Bluetooth Manager, in the New / Connect! list as can be seen in the following screenshots: 1 2. There, all you will need to do is
changing HKEY_LOCAL_MACHINE\SOFTWARE\ Widcomm\BtConfig\ Services\0005\ Enabled from 0 to 1 in the Registry as can also be seen in here. After this, a new item, Connect a headset, will be added to the above New / Connect! list as can be seen in here.
changing HKEY_LOCAL_MACHINE\ Drivers\ BuiltIn\ WaveDev\ Dll to btceif.dll. Make sure you export (or, at least, remember) the original name of this if it's different from wavedev.dll - you'll need it when you want to switch back to the built-in speaker.
Note that this tutorial also elaborates on these two steps (it, however, adds no relevant information so you don't have to read it) and I've also uploaded two registry import files to make the switch much easier. Here's the registry import file to enable sound routing and here's the one to disable it. Also note that you must reset your device after applying the registry changes as, unlike the BT stack-only hacks, which "only" make it necessary to restart the BT stack itself, the second, HKEY_LOCAL_MACHINE\ Drivers\ BuiltIn\ WaveDev\ Dll hack, will only be used after a reset because it's a system-wide hack.
After this hack, you can go on as usual: after selecting Connect a headset, the device will find the headset, you just enter the PIN (0000 or, in very few cases, 1234) and, by clicking Finish here, let the system create the shortcut for you.
Note that, despite being able to connect to the headset now, these "hacked" pre-WM2003SE devices are not guaranteed to flawlessly work with the headsets. For example, some HP WM2003 Pocket PC models are known not to be able to use them at all; for example, the HP iPAQ 4150. Unfortunately, in these cases, installing the well-known HP 1.6 BT update (see my A2DP articles on what it is) doesn’t help either: as opposed to the registry hack (which doesn’t help with this BT stack version any more) it won’t list “Connect to headset” (or, as it's called in never, 1.5+ Widcomm versions, Hands-free / Headset setup) any more in New (1 2 3) and, when you directly discover the services of a headset and select the (only) “Headset” profile they offer, connection attempts will always fail.

Microsoft BT stack
The situation is in no way so easy as with the Widcomm BT stack as it’s only with phone calls (if the device contains a phone at all) that it will actively use the headset, nothing else (for example, music, GPS instructions etc).
Therefore, you’ll need to use third-party applications to re-route the sound.
There are several solutions to this problem:
BTAudio 810 (also see this and this thread). Works great on the Wizard (with the 2.26 Molski ROM) but not on the Axim x51v (none of the audio re-routing solutions worked on it; therefore, you may end up having to install the Widcomm BT stack on it, which also offers flawless sound redirection to mono, non-A2DP headsets).
Installation: The ZIP file contains three files; just copy them anywhere on your Pocket PC (simply BTAudioToggle.exe may be enough) and, when you want to toggle the sound target, just execute BTAudioToggle.exe (or, alternatively, when you want to start/stop the sound routing, execute BTAudioOn.exe/BTAudioOff.exe, respectively.)
TP.com Btaudio (also see this) didn’t offer anything of importance in the case of the x51v either: with my AKU2.3 A12 ROM, the PDA still wouldn’t discover the Hands-free profile of my headset (only the wireless stereo, but it, in our case, has no use at all). It didn't work on my Wizard either. You may have better luck though; also make sure you read the linked thread (and also look around for other, related threads at XDA-Developers.)
Installation: The downloadable ZIP file contains a CAB file; just install it on your PDA.
Bluetooth sound: (also see this): while it’s reported to work great on the HTC TyTN (Hermes), it has no effect on the Dell Axim x51v / HTC Wizard at all (and is also reported not to work on the HTC Universal either). After installing it, BTAudio 810 stopped working; fortunately, the uninstall worked OK and, then, BTAudio 810 started to work again.
Installation: The downloadable ZIP file contains a CAB file; just install it on your PDA.
Teksoft's BlueMusic: (also see this): you may want to give this title a try too. It doesn’t work on my HTC Wizard (only if you previously enable sound re-routing with BTAudio 810; then, it’ll be able to switch it off and on but this functionality can also be used with the “original” BTAudio 810 and, therefore, there is not much point in installing (and, for that matter, paying for) BlueMusic in addition to the free and smaller BTAudio 810) and Axim x51v, but others have reported success with other models.
Installation: Install the software following the tutorial in install.en.txt in the downloadable ZIP file.
BTAudioNav by infamous PPC hacker, co-author of the Dell Axim x50/x51 Widcomm BT stack hack beemer: this hack allows for redirecting the sound of a particular (for example, GPS) application only. It also makes sure it reconnects to the headset after a phone call, unlike (some of?) the alternatives. It's available here; if you don't want to register yourself in the forum to be able to download the file, you can also get it from here (I've mirrored it there). Please see either the above (Spanish) thread or beemer's comments here for more information on the usage.
Verdict
If you have the Microsoft BT stack, check out BTAudio 810 first - or beemer's BTAudioNav. It’s the smallest and cleanest, free solution, which seems to be working just great. If you have the Widcomm BT stack, just use the built-in headset redirection capabilities (with the necessary hacking with earlier BT stacks if needed).
UPDATE (11/05/2006): discussions of this article: HowardForums.

Tutorial updated

Cingular 8525 BT Audio
Thank you for your help here. However, not matter what I've tried, I can't seem to get the audio to stream from my Cingular 8525 to my Plantronics 510 headset.
If anyone has specific advice on the 8525, please let me know.
Thank you.

HogFarmer said:
Thank you for your help here. However, not matter what I've tried, I can't seem to get the audio to stream from my Cingular 8525 to my Plantronics 510 headset.
If anyone has specific advice on the 8525, please let me know.
Thank you.
Click to expand...
Click to collapse
Strange. Have you checked out http://forum.xda-developers.com/showthread.php?t=278778 ?

Yes. I tried that. Just to be sure...
1. I uninstalled everything I tried previously.
2. Soft Reset
3. Installed the .cab at http://forum.xda-developers.com/showthread.php?t=278778
4. Soft Rest
5. Turned on BT
6. Turned on my BT Headset
7. Music in WMP and TCPMP still plays through the speaker, not my headset
Any help is appreciated.

My mistake.
I missed the part about initiating the Voice Command function from my headset. Sure enough, that did the trick!
Thanks for your help!!!!

Please help me!!!!
I cant get my blackjack to stream the music to my BT headset, I have a WEP170 Samsung headset and i cant hear the music through the headset. please help me out with this situation. the phone says that it is bluetooth mode but there is no sound in the headset.
Please Help???????

Results of BTAudio 810 on Blackjack
Prior to using BTAudio 810 on my Blackjack, I found that I could listen to WMP using a wired headset (though the volume was very low), but it would not send WMP audio to my Jabra BT350. Regular phone operation with the Jabra worked fine.
When I tried the BTAudio 810, I could hear a slight hiss in my Jabra, as if something was happening, but alas no WMP audio was coming through. Notably, WMP audio was no longer coming through the device speaker. I switched to the Notes app and recorded a note through the Jabra - that worked.
I looked around for reasons why BTAudio wouldn't work on the Blackjack, and didn't find much. There was a xda dev thread that hypothesized that Samsung had done something with the audio gateway portion of the MS BT stack.
I'm still hoping for a solution to get audio to my Jabra.

what works???
There has to be someone out there who has found something that works. i am getting desperate. i have tried every program out there and nothing works. i have the same problem. i here a hiss but nothing works. is there a hack that can rewrite the BT stack or something!!!!

newbienew said:
is there a hack that can rewrite the BT stack or something!!!!
Click to expand...
Click to collapse
You may want to check out the Wizard / TyTN Widcomm stack threads.

UPDATE (12/26/2006): Should you have audio reconnection problems, check out THIS.

Music on my Cingular 8525 using plantronics mono bt!!
Thank You!! I had about given up all hope when I transferred your cab over to my device, ran it, did a soft reset, and then pushed my voice command button after reboot. I then started my wmp and voila! Works perfectly. You are the best!!!

mshilot said:
Thank You!! I had about given up all hope when I transferred your cab over to my device, ran it, did a soft reset, and then pushed my voice command button after reboot. I then started my wmp and voila! Works perfectly. You are the best!!!
Click to expand...
Click to collapse
You're welcome and welcome to XDA-Dev

Blackjack Mono Bluetooth
Still nothing related to piping the audio through a standard Bluetooth headset on the Samsung i607 Blackjack? I'm simply shocked that the stack is implemented in such a proprietary way. I just can't seen using a full Stereo Bluetooth Headset at work or anywhere else for that matter. If anyone has any info on whether or not Samsung is planning to fix this issue (and when), please post... I'm definitely willing to wait for a fix, or even a Bluetooth earbud that supports A2DP. Thanks!

Anything that works on Trinity?

Treo 700w?
Anyone manage to accomplish this on the treo 700w/wx yet?

BT AudioNav
For the record, I used BTAudioNav for a couple of days, using it to invoke TomTom v6. The audio connection worked flawlessly, but it seemed to cause TomTom to lag badly. It consistently gave instructions 200-800 metres later than it should (distance was speed dependent). I was warned of a radar camera after I had passed it ... not fun eh?
I dropped it and went on with my search for the ideal. Just installed the Mortscript solution provided several posts higher so we'll see how things work when I drive home tonight
<update>Didn't work. TomTom failed to come through the headset. Perhaps I was doing something wrong so I'll re-read everything tonite.</update>
<ashamed>Me again ... Ignore the last load of rubbish </ashamed>
I installed to non-default places so its no wonder I naffed up! The Mortscript/Vijay solution is giving me sound, and resets itself after I've switched to voice command with the phone button, and after I've received a phonecall. Tom Tom will have to wait 'till I go home this p.m. but right now I have to say ... YAAAHOOOOOO !!

Bluetooth Sound on Dopod D810
Bluetooth sound works for me on my Dopod D810. Thanks for the info and file link!

hi,
i have an artemis, and bt audio works great to route the sound to my headset, but i want to route the mic of the headset to the phone ...
(to use with voip software, sjphone, skype)
but i don't find a solution to route mic to the pda ans not use the internal mic ...
Thank you very much

Solution for the official WM5 AKU2 MS BT stack’s disconnecting from stereo BT sets

Do your stereo Bluetooth headphones disconnect from your WM5 AKU2 Pocket PC right after starting to play anything in any media player? Here’s the solution!
I’ve often reported on a severe problem with WM5 AKU2-based Pocket PC’s (that is, ones using the built-in A2DP support in the Microsoft Bluetooth stack in all AKU2.x (and later) versions) and some? one? Bluetooth stereo headphones model, the Plantronics Pulsar 590(A/e). After initially connecting it to the originator Pocket PC (in Bluetooth Settings / Devices, clicking and holding the given headphones icon and selecting “Set as Wireless Stereo” in the context menu) and starting playing any multimedia content in any media player, the sound goes away in a few hundred milliseconds. This is the case with all AKU2+ Microsoft BT stacks I’ve tested the 590 against; for example, that of the AKU2 HTC Universal and the Dell Axim x51v with the A12 ROM upgrade.
There is a very simple but, unfortunately, (still) not widely published solution to this problem. After you’ve initially connected the PDA to your headphones (the standard, “Set as Wireless Stereo” way from the Devices tab) and the sound goes away (again), just suspend (power off) your Pocket PC (some 2-3 seconds will suffice). Then, after powering it up again, reconnect the headphones to the PDA – but, now, not via “Set as Wireless Stereo”, but using the “Establish a connection” button (which is, in most cases, the play / pause / stop button on the headphones) on your headphones. The devices will connect and voila – the transmission won’t stop any more.
You’ll rarely need to repeat this process as you will only encounter this problem only after you reconnect the PDA to the headphones via “Set as Wireless Stereo” and not using the headphones’ (re)connect hardware button. This, however, will only be needed to be used in extreme cases – for example, when you use your stereo BT headphones with more than one A2DP source and you often switch between them. Then, in order to make your current stream source the default for the headphones (it’ll always try to auto-connect to the A2DP source it was last associated with if you initiate the connection using the hardware Connect button on the headphones), you will need to use “Set as Wireless Stereo” and, consequently, the Suspend-and-reconnect-from-the-headset trick outlined above. In all other cases (for example, after powering up your PDA / headphones), this won’t be needed as you can connect your stereo headphones to your PDA with a simple Connect button press on the headphones.
(Thanks for HowardForums forum member Fire Dragan 418 for his original tip (thread here))

Tornado A2DP (i.e. bluetooth stereo headphones)

I thought it would be nice if we cfoudl get some Q&A going about this topic.
I'd like to hear which Tornado ROMs seem to have good working A2DP, which BT stack they use (if you know), what headset/remote you're using.
I'd also like to know if anyone can give use directions for checking what stack our phone is using.
I'd also like to know your opinions on volume, hiss, etc.
If you are satisfied or unsatisfied with your volume, please include your audiogain settings for comparision:
HKLM\SOFTWARE\HTC\AUDIOGAIN
(note: audiogain settings are in hexidecimal)

Here is some info on A2DP reg tweaking, that is supposed to be relevant to the WM6 bt stack.
i.e. from the "final" or "official" released, not a beta.
[ Default Settings are as follows: ]
HKLM\Software\Microsoft\Bluetooth\A2DP\Settings\
BitPool DWORD 30
MaxSupportedBitPool DWORD 30
SampleRate
UseJointStereo DWORD 1
HKLM\Software\Microsoft\Bluetooth\AudioGateway\
Capability DWORD 37
[ Aternate Settings: ]
HKLM\Software\Microsoft\Bluetooth\A2DP\Settings\
BitPool DWORD 51
MaxSupportedBitPool DWORD 60
SampleRate DWORD 48000
UseJointStereo DWORD 0
Cant remember if i changed the one below or it was already at that value.
HKLM\Software\Microsoft\Bluetooth\AudioGateway\
Capability DWORD 60
-----------------
[ Sleuth255's WM6 optimum settings for bluetooth A2DP: ]
These are applicable to the newer releases of WM6.
Finding #1:
ADD/CHANGE the following values from the registry at HKLM\Software\Microsoft\Bluetooth\A2DP\Settings :
Name: UseJointStereo
Value (DWORD): 1
What this does is enable Joint-Stereo for the SBC codec, which is important and makes the biggest significant change to improve sound quality. (Note: In earlier versions of WM5 and WM6, Joint-Stereo was broken and resulted in a mono-output. This is not the case anymore with the newer WM6 ROMS.)
Further note: Sleuth255 found that some of his A2DP headsets could not work with JS turned on. In that case, you have to set the value to 0 to disable JS (resulting in poorer quality sound with more "hissing").
Finding #2:
REMOVE the following values from the registry at HKLM\Software\Microsoft\Bluetooth\A2DP\Settings if they are present:
- BitPool
- MaxSupportedBitPool
These values are used to manually set limits for the BT stack for the A2DP SBC codec. Previously, it was thought that these values should be set between 38 to 86. But if the values are removed, I think that the BT stack automatically chooses the best BitPool values for maximum quality. I've tried removing these values and the sound quality either improved or at least stayed the same.
[ SUMMARY ]
At this point, you should have only one value in the registry at HKLM\Software\Microsoft\Bluetooth\A2DP\Settings:
UseJointStereo = 1
Your A2DP audio should be very good at this point - almost indistinguishable from a wired headset. However, if you are still unsatisfied with the sound (you may notice some very slight "hissing" or "swishing" sounds on high frequencies of certain songs), you may want to try the optional setting below.
[ OPTIONAL ]
Finding #3:
This is optional, and a matter of preference.
ADD the following value to the registry at HKLM\Software\Microsoft\Bluetooth\A2DP\Settings:
Name: SampleRate
Value (DWORD): 48000 (decimal)
This forces the A2DP stack to send the audio to the headset at 48000Hz instead of the default 44100Hz. For some reason, I find that the 48Khz value makes the "hissing" sounds less obvious. Your findings may vary, as some people may prefer the slightly more forward sound of the original setting. But if you are game, give this a try - one thing for sure is that it definitely changes the sound quality.
To reverse the change, just remove the SampleRate value.
If you make this 3rd optional change, you should have the following values in the registry at HKLM\Software\Microsoft\Bluetooth\A2DP\Settings:
UseJointStereo = 1
SampleRate = 48000
[ Note - Quick tip on registry editing ]
Of course, every registry change needs a soft-reset to take effect. And please take the usual proper care when editing the registry or risk damaging your device.
Find that your settings dont "stick" after a reset?
Make sure you reset the phone like this: After making changes to the registry, exit your registry editor. Then push the power button of your phone (putting it into standby, with the screen off). Wait for about 10 seconds (the phone will be saving the data to disk during this time), and only after that push the reset button.
Click to expand...
Click to collapse
I like to quote my sources, but I don't have the links at this moment. I will update them later.

Varied...
My experience across four or five builds has always been mixed. My older Motorolas work fine but my newer S9s dropout periodically. Interestingly, not all builds have the same result when I use them for handsfree. Some builds give me the voice I am speaking to in mono and some in stereo. Currently I am using Nitro's build from a month ago.
I have already exchanged the S9s once, so it wasn't specific to that one headset.
Exitao - Do you have dropouts periodically? What headset do you have?

kkrull said:
My experience across four or five builds has always been mixed. My older Motorolas work fine but my newer S9s dropout periodically. Interestingly, not all builds have the same result when I use them for handsfree. Some builds give me the voice I am speaking to in mono and some in stereo. Currently I am using Nitro's build from a month ago.
I have already exchanged the S9s once, so it wasn't specific to that one headset.
Exitao - Do you have dropouts periodically? What headset do you have?
Click to expand...
Click to collapse
Sorry, I was intending to post my personal details soon.
I am using a Sonorix C3
Standards Bluetooth Specification V2.0
RF Frequency Range 2402 ~ 2480 MHz
Profiles Supported A2DP, AVRCP, Headset, Handsfree V1.5
Transmission Power 0.25 ~ 2.5mW (Bluetooth Power Class 2)
Receiver Sensitivity < -80dBm (PER 1 %)
Distance 10m (in open space)
Click to expand...
Click to collapse
I am using EA's Chinese "WM6 5.2.318.18120" ROM:
http://bbs.koxo.cn/thread-14687-1-1.html
Currently my headset (well, the remote dongle, really) supports stereo playback, call display and bt handsfree usage.
Reception seems very clear. Mic pickup is sensitive and noise cancellation seems to be just as sensitive (I was holding the mic in my hand and gesturing madly one day, and realised what I was doing).
My only complain is the volume. I need to muck about in the audiogain settings to increase it.
As for what bt stack I'm using, I have no clue.
If I dump the zip file from this link, http://forum.xda-developers.com/showthread.php?t=263735&highlight=a2dp the bta2dp.dll was last modified on april, 2006. When I look in the windows directory of my phone, it only tells me I flashed it. I guess I have to dump the ROM to find out.
There is also the problem that the WiMP in my ROM can't handle VBR files. I'll be updating to vjgrace's 3.5 ROM shortly.
edit:
No dropouts. Mostly it is a fight to manage system resources on the phone.

any ppl know how yo make when the phone ringtone can ring in bluetooth.
mean we can listen the ring tone from bluetooth.

Terrible bluetooth audio quality after upgrading to WM6.5 (Touch Pro2 WWE)

Hi all,
Before upgrading my Touch Pro2 WWE to WM6.5 I was perfectly happy with the bluetooth sound quality. Sure, I did tweak it using a registry editor (months ago, I don't recall the exact changes I made), but the sound quality was marvellous. And...: no hickups!
As probably most of you already did, I upgraded my TP2 to WM6.5 about two weeks ago. So far I like WM6.5, I even get the feeling it has a slight better battery usage.
However, there is one big downside to this upgrade operation: I can't get the bluetooth audio quality on my Jabra headset to meet the quality it had on WM6.1. I used a registry editor to tweak the BitPool and UseJointStereo settings, but still I constantly have the feeling I'm listening to 96 kbit/s MP3 files, whilst the files are of >= 192 kbit/s quality... Also, music sometimes just 'hangs' (silence), and continues after a few seconds.
Am I missing something? Are there other parameters I need to tweak? I'd like to know which settings you guys use. Thanks!

Hi all,
I have the similar problem on my Diamond2. But I didn't used bluetooth headset while having WM6.1, so I can't tell was the audio quality good or bad.
I have silence gaps of 0.5-2s all the time listening to music. The gaps length and frequency doesn't seem to depend on the distance or obstacles (reasonable ones) between the phone and headset. They can be one inch one next to another but the gaps will be present.
However, the audio quality seem to be good.
I have TDiamond2(first official WM6.5 ROM from october 2009) + Jabra BT620s. I've tried various registry tweaks found here and in internet but with no result. Maybe I've missed somthing. Any ideas what might cause gaps?
Thanks in advance!

I think I just found a (the) solution! Check out this post at smartphonemag.com:
http://www.smartphonemag.com/cms/blogs/3/1350#more1350
Particularly, look at the LineSpeed DWORD, located in HKEY_LOCAL_MACHINE\SOFTWARE\Widcomm\Plugin\AV
Setting it to 320 and resetting the bluetooth functionality led to a considerably better audio quality. Other settings which I have changed (don't know if they're relevant):
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Bluetooth\A2DP\Settings
BitPool = 58 (DWORD)
SampleRate = 48000 (DWORD)
UseJointStereo = 1 (DWORD)
(all decimal values)
Good luck!

Windows media runtime mobile?/native arm(?) wav format?

Hello. I have managed to somehow damage the setup of WMP in my device and am quite happy with it - it wont fight with better players when using bluetooth dongle's HWbuttons. It is dead for good
The problem is also mp3 ringtones wont sound anymore ("ringtone is corrupt bla bla...") so I have converted them to wav but it seems that loading wavs in the call state is aggravated - the sound is sometimes a bit choppy.
So I have thought of two solutions and haven't reached any of them yet:
1) to get a WM runtime for CE but is there any?
2) find out what is the most native wav bitrate (8/16), sample rate(11kHz-44kHz) and number of channels (1/2) for the chipset - does anybody know?
Thanks for reading

one would think that hardreset would fix your problem
about the best wave setups then it really comes down to what the pretty small speaker unit can produce
of cause it would not do stereo being only 1 tiny speaker
16bit would not be notiable on such a small speaker I think
and landline phones used to use a samplerate of only 3Khz and their speakers was better then new cellphone speakers
I would make various versions of the wav and compare if I could hear any difference

Rudegar said:
one would think that hardreset would fix your problem
about the best wave setups then it really comes down to what the pretty small speaker unit can produce
of cause it would not do stereo being only 1 tiny speaker
16bit would not be notiable on such a small speaker I think
and landline phones used to use a samplerate of only 3Khz and their speakers was better then new cellphone speakers
I would make various versions of the wav and compare if I could hear any difference
Click to expand...
Click to collapse
Thank you for your answer.
I am not after the sound quality. And hard reset is not needed as the only circumstance that would lead there is that media player is not working but I am happy that it is crippled. So if there is not any runtime of wmedia I am just interested of the fastest renderable wave format for my kind of device (see signature) that has bypassed the wmedia boundary and suspectably plays it some kind of "straight/raw" method. I've got a feeling that it is not the lowest (for example mono 8bit and 6kHz)

Database Info

welcome