I have an AVH-P4000DVD and the CD-I200 iPod cable. When I connect my 2g iPod Touch the unit switches to the iPod and shows activity like it's playing, but there's no sound. I tried connecting my dad's 5th gen iPod and got the same result. I can control the iPod through the head unit but there's no sound. I also have the CD-BTB200 Bluetooth Adapter and the GEX-P10HD HD Radio Tuner connected through IP-Bus but I doubt they are interfering at all. I searched and found a similar topic but no one gave a definite answer:
http://avic411.com/forum/viewtopic.php?f=16&t=19604
Any help would
