Radio Unit iPod Wiring Problem - Audio Gurus Please Help!

Hey Gurus,

I just installed the USA-SPEC PA 12 Unit onto my vehicle but I am getiting no audio. The car is able to read the unit but create playlists but no audio is coming out. I suspect it is a problem with the radio unit and I found that the wiring for the iPod is not plugged in on the radio unit. I can't find where the plug for the iPod wire plugs into, am I suppose to unplug something?

Here are some pics.












Gurus, if you are out there, Please advise!

Thanks