I got the orbital double din, installed everything and have put the harness into the Avic Z2 and I get no sound out of my speakers... There are two things that were plugged into the back of the original infinity system... One of which is a single black audio cable that I've plugged into the the back of the Avic, the other one there isn't a spot for, but I was told it wasn't necessary. What am I doing wrong or how can I fix this??? Thanks Matt

PS (I tried my stock headunit and when (harness, single black cable and other plug) are in it works)