ah, your only using the USB input arnt you? the usb controls the ipod and the 3.5mm jack is for audio and video. if you look at a normal 3.5mm plug it has 3 sections, ground, + for left channel, + for right channel. the one you need for this hu has 4 sections, the extra is for video. your ipod's 3.5mm output is only for audio so it only has the connections for the 3 section plug. you need to get the pioneer cable for this to work.