I have a DEH-P4300R with CPX-P670 changer. According to the manual, the 4300
can only control 1 external unit at a time. I also have the CD-RB20 and
CD-VC60 connected through the bus connector with no problem. However, I
wouldn't mind having the ipod interface connected as well. I've been told
that with having the CD changer, it is not recommended having the ipod
interface because the head unit can only cope with 1 external device. Can
anyone confirm that? It seems a bit strange that since the CD-VC60 is
classed as an external device, that the head unit is ok with that and the CD
changer.