I just bought my third Audi: A nice 2002 2.7T A6 with all the trimings. I think that the car had a car phone installed, since it has an external antenna mounted on the rear window, but I don't see anything inside. The radio has static noise on weak stations which appears only when the car engine is running - but disappears when only the ignition key is on or off. The Symphony has an active noise reduction system (?) or might it be some interference with that old phone antenna? Dealer was no use. Thank you very much!!