Yes, your unit is working. Whatever the problem was is physical in nature, not an electonic failure.

You must find the correct screwdriver and carefully remove the motherboard. If you do have a loose screw that was causing this problem then you need to remove it before it gets somewhere else and causes permanent damage. If this is the problem, then _expensive_, or possibly _irreparable_ damage is a real risk.

Until you do this, I'd recommend disconnecting the power and leaving it so. If you want to check the disks and can carefully do so without disturbing the player physically, then that's your choice, but I personally wouldn't.

The only other cause that I can think of is a bad solder joint - but apart from the IDE header issue I don't recall ever hearing of any.

[edit] Reinforced my statement about checking for screws.