Sony DVD RW problems
 

Hi folks, having trouble with this DVD burner, factory installed, it is a Sony model RW DW-D22A, until recently worked A-ok.
It will not read data cd's or play audio cd's, but it will run DVD's. When I load these type I hear a few small attemps at the drive to read, light blinks a bit and goes off, and there is no data to display.
My son has burned DVD's on it recently without any problems. Now it does no other function.
Anybody please help if you have knowledge.
Thank you