May be I can help you both. Can you take some pictures of the back of the unit and wire harness? I just bought a 05/2002 X5. I should try to install my homemade aux cable ($12) this week end. I need to unplug a wire and reconnect the plug according the instuction. I have installed about 10 aux-in cables before. Believe me, the sound quality are much much better with the direct aux-in.