Hey if it's under warranty, let them take care of it. As long as they work with you that should be all that matters. You may get a new radio out of it. If you are dead set on trying to fix this yourself, get a cleaning disc and try that. That's about all you can really do w/out taking the thing apart and trying to manually clean the laser. That is, of course, assuming that's all that's wrong.Tell it to "fcuk off" in a stern tone and it should work.
Also, feeding the CD drive some pieces of white bread can help. Do not include any hummus on the bread as that could result in an irreversible "Error".