Is a pinout diagram/description of functions available for the D connector that attaches to the back of the radio from the sat radio, remote cd or Phatbox in the '04 B6 S4 & A4? I have seen the identification of the ground and signal pins for the XM-Phatbox mixer. To try to cobble up a switch for those signals, I need to know what happens on what pin(s) when the Sat/CD switch is toggled on the head unit.
Of course if there is a switch box or plan for one available, I'd be interested in that. (I wouldn't have to display how electronically challenged I am if there's something that is already plug and play.)

I found Jeffrey Sessler's pinout diagram for the Concert. Pins 18 to 20 seem to have the same functions that I have seen reported for the Bose Symphony II in the B6. Does anyone know if 17 is still a switched power line for the remote CD?