For reasons beyond anyone’s understanding, Apple sets OS X’s bluetooth audio quality quite low, this is probably to allow for better bandwidth, but still.  When I first read the bluetooth quality setting here’s what I found:

1 2 $ defaults read "Apple Bitpool Min (editable)" 2
To improve overall streaming quality for your Bluetooth audio, set it to something like 40:
1 defaults write "Apple Bitpool Min (editable)" 40
So much better.

[Update:  20130812]:  I found a bluetooth log that you can enable if this doesn’t fix your problem.  By reading through it you may find additional information about your problem.  To enable the log:

1 2 sudo touch /var/log/bluetoothAudio.log sudo chmod 777 /var/log/bluetoothAudio.log
That file should now be written to, constantly, when you’re using Bluetooth Audio.  Just be sure to remove the file when you’re doing troubleshooting, otherwise it will keep logging data there.