I have multiple stereo A2DP headsets (moto ht820 and s9 and a blueant) and they all work fine. I don't have any experience with mono A2DP so I probably won't be too much help. I just tried to do music through my Jawbone 2 and it didn't work. I would suggest when you connect the headset, make sure on your berry it lists headset, audio, etc. I don't remember exactly what it says but it should say "stereo audio" or something like that. Don't know what it would say for mono though. If you still can't figure it out, try emailing the headset manufacturer or looking in the instruction manual.
Semper Fi,
~Marine39
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