This has happened to me too. It was "fixed" by unplugging the power from the radio for several minutes and then plugging it back in. It has been working now for almost a year. Obviously, I have no idea what happened but it worked.

If you want it to be perfect try Becker http://www.harmanbecker.us/ - but it's really expensive. When I called they wanted $120 just to clean it and recalibrate the tuner.