Improve Bluetooth Audio quality under OS X
Bluetooth audio devices often suffer from a bad audio quality under OS X. To improve audio quality, OS X allows a few settings to be made with terminal.

Enter the following command:
defaults read

This should print the bluetooth bitrate settings which look about like this:
  "Apple Bitpool Max (editable)" = 64;
  "Apple Bitpool Min (editable)" = 2;
  "Apple Initial Bitpool (editable)" = 40;
  "Negotiated Bitpool" = 40;
  "Negotiated Bitpool Max" = 64;
  "Negotiated Bitpool Min" = 2;
  "Stream - Flush Ring on Packet Drop (editable)" = 0;
  "Stream - Max Outstanding Packets (editable)" = 30;
  "Stream Resume Delay" = "0.75";

To improve these settings, do the following:
1. Disable bluetooth and exit all audio programs (iTunes, ...)
2. Enter the following commands into terminal:
defaults write "Apple Bitpool Max (editable)" 80
defaults write "Apple Bitpool Min (editable)" 53
defaults write "Apple Initial Bitpool (editable)" 40
defaults write "Negotiated Bitpool" 58
defaults write "Negotiated Bitpool Max" 58
defaults write "Negotiated Bitpool Min" 48

3. Restart the computer
4. Verify the parameters by entering again the following command:
defaults read

admin / Oct 31, 2014
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