According to this article at ppc magazine, JointStereo = 1 retains stereo seperation in Windows mobile 6:
http://www.pocketpcmag.com/blogs/ind...&c=1&tb=1&pb=1
He basically says that all you need to do in WM6 is remove BitPool, MaxSupportedbitPool, and maybe add SampleRate 48000 if you think you need it. I think he is right.
I set JointStereo back to 1, deleted bp and msbp, then I added the SampleRate 48000 dword. So far it sounds great with zero skipping.
I am pretty sure I hear the separation in the Gorillaz "O Green World" on Demon Days album. I am still looking for a better sample song.
Also, I read this interesting article on Joint Stero:
http://harmsy.freeuk.com/mostync/
Apparently, according to the article, the use of proper "Joint Stereo" does not eliminate stereo separation. Not exactly sure if this applies to A2DP bluetooth, but I suspect it is the same concepts.
edit: edited SampleRate 4800 to 48000 above