If you are using a Headphone Jack from the iPod to the AV In, with another Headphone Jack, press and hold TV Button for a few seconds until it displays AV in your Screen. It will appear black. Press the play button on your iPod and you will hear it. Volume can be adjusted from the steering controls, but not the selection.

FYI, sound isn't so great coming out of this. I wonder if the iPod attachment would be better? Anyone else has any experience in this?