Edit: What am I saying? I'm acting as if the warranty seals have any meaning whatsoever when I'm advising the guy to open his player on a public forum that's read by the very people who do the warranty servicing.

Just peek inside the player and be really careful. It's probably just a loose cable. If not, then call support right away.

if it is a loose cable, he won't be able to re-attach it without breaking the seals.

First thing I would do is like Tony said, fire up hyperterm and see if the player finds any disks when booting. My money is also on a loose drive cable though.