hi there, i'm a new member with a bit of niggling problem with my a4 avant. I bought the car 9 months ago, but failed to notice some of the buttons on the standard single cd stereo weren't working (even after problems with my 1999 a3). if you can imagine splitting the head unit down the middle, between 3 + 4 buttons, the whole of the left side isnt working with exception of the on off volume toggle, yet all on the right hand side work fine. The radio works, but cd doesn't. is this a common problem, can it be fixed, or do i need to buy a replacement unit from ebay?