Help!

I bought a Fuze just recently, primarily to play MP3 Audiobooks. I read the forums, I followed the instructions and copied the MP3 files into the audiobook folder in the device.

I started listening to the audiobook, chapter 2 was announced and then the screen went black, the wheel light remained on, the power switch would not work. NOTHING. I thought it had died. 

Actually, I had started listening to this very same Audiobook a couple of days ago and got through Chapter 3 and turned the machine off. I'm not sure why the second and third time I tried listening to this audiobook, it locked up the device.

Then the next morning, it was fine. I tested the track on my PC, through windows media and it played fine.

Any help would greatly be appreciated.