I have played audiobooks and mp3's on my 720 with 8.302 or whatever version it was for a month or two with no issues. Since updating to 8.35, I now have issues with an 'Error during playback' message when playing mp3's. I have tried various files and all have the same playback problems. A pin reset worked for about a day. The error returned the next time I tried to play a file. A pin reset every day is not a good remedy.