I think I would just keep the jukebox you allready have got, leave the IP bus (cd-changer-bus) connected to that, and the RCA (I think sony use RCA?) from the jukebox to aux-in on the RioCar/Empeg, and then RCA out from the RioCar/Empeg to RCA/cdchanger in on the Head unit. This way you would get music from the empeg played through the main unit, and you could use the jukebox with the empeg in "aux" mode.

You would not be able to "remote control" the 'RioCar/empeg from the Sony headunit though.

Marius (Escort Cab + Mark II)