I want some how to use the CD changer (M-BUS) port for the aux input on my Alpine HU. There is no way (i know of ) doing it without a CD changer. Most newer M-bus HU has a mute line. Ground the mute line -> enable aux input thru changer port. This HU doesn't do that. It's an old M-bus HU (pre 95 model).
jbor do you have any idea?