If you mean the Sony Model # ICF-CD815. A.K.A. Dream Machine
you should check the user manual, for troubleshooting instructions:
from the manual:
The CD player does not operate.
- Did you close the CD lid?
- Did you place the disc correctly?
- The disk should be placed with the labeled side up.
- Dusty or defective disc-Clean the disc with an optional cleaning cloth. Wipe the disc from the center out
- Take out the CD and leave the CD compartment open for about an hour to remove moisture condensation.
It seems to be a top loader system, so a few checks are in order:
- Check that the disc spins (Insert CD, try to play and open the tray) Be careful, the disc might fly out of the tray!
- Clean the CD drive lens with a cotton bud and some optical cleaner (camera shops and radio repair shops/techs should have a suitable liquid)
If the unit seems totally broken, take it to a tech or recycle it at a waste electronics depot and get a new one.