Sounds like the base for the Sat. Rad. unit is bad, not an uncommon thing. Usually it's the Sat. antennas that go bad though. Use the headphones like stated above, should be a pretty clear test. If it doesn't pass, some precision screw driver set should allow you to disassemble the unit. You may be able to use some solder to fix your issue. I've been able to do this with the bad sat antenna connections before. If that doesn't fix it, time to order a new base, or in some cases, if you've been a Sirius customer long enough, they'll send you a new base or radio unit all together to keep you as a customer instead of losing you.