(Update Programming RCD-510 Radio (Premium 8)):
Programming contained in software level(s) for certain RCD-510 Radio (Premium 8) radios may cause Bluetooth audio quality complaints for model year 2012, and 2013.
The production solution for this issue is a running software change.
This document discusses the "Fault Codes" necessary to diagnosis, and potential remedy of the issue. The fault codes for checking warranty coverage for servicing the vehicle are also available.