I picked up a D604 cheap at a garage sale not too long ago. Get it home, and the machine plays LDs but not CDs. Strange, and opposite of the norm. The player starts to spin up the CD, but never recognizes it. It then slows down then spins it up again, again failing to recognize. You never hear the lens focusing. It then ejects the disc with a PS error. I have tried changing the loading belt, and that didn't change anything. Any ideas?

Edit: The error could be P5, not PS

Sounds like an issue I had with a CLD-79 I had. Can you access the digital tracks on an LD or does it only play the analog tracks?

My guess is the spindle motor is not centered with the laser properly. This is more critical playing CDs than LDs

Is there a way to fix that?

There is a black tab behind the spindle motor on the left side you can put a screw driver and adjust. Normally when a CD is playing, if you don't have an oscilloscope, you play the CD and find the two extremes where it starts skipping and center the adjustment between the extremes. In your case remember where you are starting at. Move a little CW and try a CD, then move a little CCW and try a CD. If you get the CD to work then perform the centering process.

Thank you, I do have an o-scope though if I can get things more accurate with it.

Got it working just a few minutes ago. It was not easy to get at that adjustment either!