I think i found a bug with aosp. My google music occasionally works, but most of the time when i try to play offline files i get the error "couldn't play the track you requested". Sometimes they will play, and the stock player plays them fine.
I initially thought this was an issue with my damaged SD card, but it kept happening after i stopped using an SD card, then it kept happening after i got a new one. I have tried several fresh installs, nullifying, installing google music from apks, installing from market, transferring my mp3s between internal and external storage, and i have even tried redownloading eaglesblood incase i had a corrupted rom file.
When i go back to a cm based rom the problem goes away.