I'm installing a factory 6 CD changer in my 2004 X5 w/DSP and the kit came with a DSP cable. I plugged in the 3 pin power/I BUS connector, and the changer works fine with the 6 pin connector installed. But what about the coax cable that I got with my kit? I bought the kit from Bavarian Autosport and their catalog noted that the cable was required for DSP systems, but I can't figure out where to plug it in? Any help would be appreciated.