have you tried removing the batteries from the radio and mp3, and reinstall them
after 20 minutes or so ?
have you tried to run the 1121 without the mp3 installed ?
make sure all batteries are fully charged / or new batteries used to test.
try these easy tips and let us know how it went...
you may have a defective mp3, which can be replaced for 50 bucks
check posts for info...