Last weekend my windows started acting up in my 2002 A4, 3.0 Quattro. The window switch does not work at any window in the car, except that I can control any window but my own from the switch on the driver's door. The sunroof works fine, and when I use the key in the door lock to open or close the windows, all of them operate except for the driver's door window. Does anyone have any suggestion as to how I can fix this?