Audi Bose Concert 13pin Connector Pinouts

[Olly_K]

In desperate need of help here guys, i've bought a aux-pod in the US which basically hardwires in my ipod through the 13pin socket found in the boot of my avant, (and on a6s, etc). Trouble is, it doesn't work. When connected, it will charge my ipod, and flick the head unit over into "aux" mode, but no sound come out and I can't control the ipod. Having though it was faulty, I sent it back to the US, only to find that they've tested it and it works fine. So something must be different in the way the 13pin connector is wired.
Does anyone know what the pin outs are on the 13pin cable in the boot ? ie, does anyone know exactly what pin does what ?
My stereo is a single din BOSE concert, if it makes any difference !

Many Thanks in advance !