Inconsistent A2DP Performance Solved!
As long as I have had my Verizon Galaxy Nexus I have had trouble with the Bluetooth phone and music features. The (completely stock) phone would not auto connect to my car's hands-free phone reliably and the A2DP protocol would not connect to my Bluetooth music receiver in my car reliably. The fix for the hands-free Bluetooth phone inconsistencies turned out to be with airplane mode. I was using Automateit to automatically put my phone into airplane mode each night and awake it each morning. Disabling that command has allowed my hands-free Bluetooth phone protocol to connect reliably every time without exception (going on several months). Re- enabling the Automateit auto airplane mode command resulted in the same unreliable phone connection, leading me to believe that there is a bug existing in airplane mode that affects the way the hands-free Bluetooth phone auto connect features work.
A similar area of annoyance regarding A2DP functionality seems to have been resolved using Automateit as well. My car does not have built-in Bluetooth A2DP so I purchased a small A2DP receiver that plugs into the aux in port on my car stereo. The problem was that when I turned on Google music and the Bluetooth receiver it may or may not play the music, and would frequently drop the connection and try to reestablish. The drop and reestablish cycle would go on until I shut Google music off. I then found that toggling Bluetooth off then back on would allow a reliable A2DP connection. Using Automateit, I set up a rule that has Bluetooth turned off when within range of a recognizable wifi signal (so when I am not in the car). When out of range of wifi, (which most likely means I am in the car) Bluetooth is automatically enabled. What I found was that not only did my phone and A2DP features work perfectly and reliably, but my battery life was greatly improved as well. I'm not sure what the common wisdom says but it appears having Bluetooth always on is a huge drain on the battery of my VGN. Anyone suffering from the same symptoms download Automateit and give it a try. Three weeks after setting up the auto Bluetooth off / on commands and not a single problem- with the added benefit of better battery life. (I get over 2 days of battery life (using the 2100mah battery) with 30% screen-on time with light use. I took a screen shot of the battery usage chart.