iMac immediately ejects CD

[naturallight]

Hi
My new iMac can't seem to read CD's. When I insert a CD, it attempts to read it for about 5-10 seconds, and then spits it out.

Help! This doesn't seem normal. Is there anything I can do other than send it in for a repair?

 

[Eidorian]

Does this apply to all optical discs? I'd try resetting your PRAM as well.

 

[sushi]

Is the lens dirty? Have you tried using a CD Lens Cleaner?