Have you tried a laser cleaner disk?

Also try cleaning the CD's.

I'd recommend against using the CD cleaners that use the brushes on the bottom. They are just as likely to change the critical alignment of the laser as they are to do any type of real cleaning.

Many new products use microprocessors (much like computers) and occasionally they lock up. Try disconnecting the power to the unit for 10 minutes (to allow the capacitors in the unit to fully dissapate) then plug it back in and see if it functions normally. The reason that I recommend unplugging instead of just hitting the power button is because many electronics leave part of the circuitry powered up at all times regardless of the state of the power button.

Recommended the cleaner disc because I had a ADCOM unit do the exact same thing after I moved it cross country and a 3 minute sweep with the disc fixed the issue. Dust is not or friend.