Hi guys,

I have just purchased a 2001 A6 Quattro. It has an Audi Concert headunit (cassette / radio / 6 cd changer).

In the glovebox, there is is a cable with a headphone jack at the end. Excitedly, I plugged it in to my ipod (then tried iphone 4) but could not seem to 'select' the aux input.

When I press the 'Mode' button, it switches between CD and Radio (interestingly, will not switch to Cassette). The CD changer still seems operable... as I switch through each slot, it says 'No CD' (correctly, as they are currently empty).

Does anyone have any idea what the cable might be for? If it is for an ipod, how would I select it? As I say, I played the ipod and then tried switching through CD (and each slot). Not sure what else to try.

Would really appreciate any advice, as I am completely stumped