Dea,
I believe the drawer drive belt is worn. I am having the same probelm with the same model of Yamaha cd changer as you as well as another Yamaha model.
It is a cheap fix and you may be able to do it yourself. See if any local repairer has small CD player drawer drive belts first!
Good Luck!
TLK
Greensboro, NC
TLK, April 2007