Just to let you know as an //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif all of Kenwood's eXcelon HUs from 2004 and newer will support the function you're after. The HU connects to the lead amp via the cable like what is supplied with a Kenwood CD Changer and any amps beyond the first connect to each other via an S-video cable.looking for x679 x879 or x979