Ok, so I have my UK spec 2003 Audi A4 and in the span of a month both my glove box CD changer and Audi Concert Head Unit CD function have quit working.

I am assuming that the Concert Stereo IS NOT the same as Bose. Anyhow, is there a wiring adapter to use when swapping at the head unit? Is this an Audi part? Any suggestions on what head unit (under $150... it just has to work).

Note: In the UK spec Audi, the Concert stereo includes a rear deck mounted subwoofer.