I woke up this morning and used my apple remote to wake my MacBook, then hit play again to start iTunes playing. Nothing happened. I verified that the sound was turned up, to maximum. And on closer inspection found that iTunes had started to play a song, but was making no progress in actually playing that song - the progress bar was stuck at 0:00 and skipping songs or scrubbing within a song makes no difference. Restarting the application made no difference. All of my music is 128kbps m4a and I also attempted to play m4v files, with a similar lack of success. I am running iTunes 10.0 on OSX 10.6.4, and I have modified the .plist to restore the coloured icons, as well as using the terminal hack to restore the traffic lights to the correct orientation. Any advice as to what to do would be greatly appreciated.