Solar Powered Radio ?!?
 

I have a 2001 A6 with a Bose Symphony radio. The radio only works when the sun is shining into the windshield. In the dark there is nothing but "static" and noise. Even when I drive through shade the signal weakens. When I pull into the garage the signal weakens and fades away into static and noise.

Anyone have any ideas? Is it possible the sunlight sensor in the climate control system could be effecting the radio?

:) It could be an answer... I do not know much but as I read it I cannot think of other explanation!