Yes, there is a way to clean the Laser lens on your player. You can find it at Wal-Mart, Best Buy or Circuit City. On your receiver, see if you have an Aux input. If you do, connect your CD to that input and see what happens.

Is the Sony sitting on top of the Yamaha?

NO, the other way around. The speakers were on top of the cabinet that holds the two units, so I moved them away last night and sure enough, even on lower volumes after about 15 min, it starts skipping badly. I've been doing research and posting in other forums and the concensus seems to be that Sony's are notorious for skipping and there's pretty much no repairing it (just not worth it). I have LOVED this unit for 5 yrs, keeping all 400 cds in one unit is such a time and space saver. I think it's time to try something else ?? Anyone have a cd player that holds 300-500 cds and doesn't have this problem ??