Bluetooth A2DP Sound Quality Widcomm Stack
 

I know a few don't like this bt stack because of the stereo quality. There is no bitpool settings but a LineSpeed tweak.
I just got my phone today (of course I used a customize rom) and didn't like the breaking of high frequencies so I went searching in this forum and xda. I found this post, giving all the credit to the poster of this...

http://forum.xda-developers.com/showthread.php?t=525050

I used Resco Explorer Registry add-in to add the following DWORD value:
HKLM\Software\WIDCOMM\Plugin\AV\LineSpeed
Value = 300.

This make my Sony headset sound clean. Hope this helps.

Attached is the registry file to import with your favorite reg editor.