[Headly]

It is possible that it is other things but my number one suspect would be the cable that goes to the motor to move the laser across the disc. This cable pulls out rather easily and does not have one of those snaps on top of it to hold it in. It is also the shortest going to the board so if the other end of the board isn't supported it is the first to fall out. Listen to your drive, is it spinning the whole time or does it stop?