Just got the Android M update yesterday on my Nexus 5. Plugged into Android Auto for the drive home and found that media is playing through the phone rather than the head unit (8100NEX). Regular Bluetooth audio streaming (wireless) works so this is something new under Android M when connected to Android Auto.
If anyone has M + AA, can you comment on how this is working for you?
If anyone has M + AA, can you comment on how this is working for you?