Jay, there is probably something wrong with the transport. As I said, something could be out of alignment. What is the model number of the Sony player you have?
I assume the screeching noise is emanating from the CD player. If that is the case, it could be a mechanical issue. It is possible that something is out of alignment in the transport (clamp, drawer, etc.). Do you hear screeching when you begin playing a disc or does it happen at random after...