CD player will not spin with CD in it?

I have a personal CD player (no name brand) that started giving me trouble last night.

When I put a CD on the spinner and push it down (locking it into place as I have always done), it will not spin. However, if I just sit the CD on top of the spinner, it *will* spin, but of course, the CD is not secured and falls off.

Does anyone have any ideas as to what is wrong with it?