My 03 exhibits a similar symptom once in a (great) while. The problem is related to the firmware in the radio/stereo.

There's a TSB on this I think but since my car's out of warranty...

What the tech told me I can do is remove the fuse that controls the radio/stereo circuit to remove power from this circuit. I don't like this and never bothered to learn which fuse is which.

Or, he told me, I can turn off the key, killing the engine, and wait a while and let the circuit power down on its own.

Since this radio symptom happens so seldom I simply do without the radio and the next time I get in the car the symptom is not present.

Sincerely,

Macster.