CDX-GT50W hardly plays burnt cds, and wont play...

OK, my girlfriend bought me this for christmas '07, and I hooked it up with no problems as usual. It worked fine for 6-7 months, then started making some kind of noise somewhat like fishing line being pulled from a locked reel. Kind of a sickening noise , in short intervals. It sounds like it is trying to read the cd, but then also sounds like it's not spinning it very well. I guess it kind of sounds like maybe a rubber wheel trying to spin the cd or something, but not getting full grip, and vibrating it.
Anyways, that's a new cd. I've put a a few cd's in that I didn't know were even going to play they were so scratched, and it played those fine. I don't know , it also doesn't specify what fromat is being played. I thought my manual said it did. She paid $150 for it, and I am trying to decide whether this will be an easy, cheap fix, or if I should start looking for a a new stereo.
Any help would be appreciated, thanks for your time, tim