Okay, I guess I am not as concerned about this problem now as I was a few days ago. I was just initially concerned it was a sign that my hard drive was going out.

Since my original post, this has happened three more times.... but I got the seemingly more common 'Failed to unmask IDE' message every time. This shows as the last line on the boot up screen before it halts, where as the hard drive message was a fresh screen with only the error text in a larger font (looked fairly severe:).

It is odd that I got the hard drive message the first time and the IDE error every subsequent time. I haven't changed anything on the player - haven't even done a sync since the first hard drive error message. Probably some low level OS thing that I could never hope to truly understand :).

Thanks for the reassurance!