Why would my CD player start skipping?

My Pioneer PD75 CD player has recently started skipping on almost every CD. I've cleaned the CDs and cleaned the laser but it still skips. Anyone know what might have caused it to start skipping. I have an authorized Pioneer service center within a couple hours drive.
Could be many things; very likely the laser beam head has gotten out of alignment, just from long-term use. If so, a technician should be able to align the heads.

Secondly, Is the transport stable? Any vibrations?
Laser pickup may need an alighment or even complete replacement. Dando Electronics in Kansas City, MO 816)361-6733 can handle the job
Try taking a can of compressed air and dusting of the lens
it just may be dirty
Elevate the front two feet ever so slightly. Sometimes thats all it takes to have the beam track the disk properly.
Try playing some Brahms. Nothing can skip to music like that!