Thanks for the tip.
In case anyone is confused as to where to install an iPod/iPhone adapter in a C5 A6, here are some pics:
First dropped the glovebox:
Taped up the Enfig unit (yours could be Dice, USA Spec, Grom...etc)
The Enfig unit came with a heavy duty albeit overkill 8 gauge iPod cable....about 6 ft long. Had to tuck it away in the glovebox too.
Tuck all the wire connectors in the small cubicle to the right of the headunit.
Re-assemble and end result!
Also Enfig had DIY videos apparently, would have been nice if they mentioned this ahead of time...could save me and many others a lot of time!