Protron DVD home theater system BROKEN!

We bought a Protron DVD home theater for christmas so it is only about 3 months old...it is stamped Q2 2005 model pds 2315. It will play Compact discs and will also play the lens cleaning cd but keeps telling me "wrong disc" when I insert a DVD...Has anyone else had problems with this brand or know of any way to fix this problem?? Your help is appreciated.