I need help finding out what is wrong with my 6 Dics CD Changer!?

I have a 2003 Chevrolet Tahoe LT and every time I put a disc in the check disc message comes up. I've tried brand new cds and everything. The disc only stays in about 10 seconds and than comes right back out. I tried one of those lens cleaners but it spit it right out too. Can someone help me please? I need my cd player!