this is so frustrating...and im a girl

all my wiring is correct i believe. my aux is on, mute i tried both on and off and the same with the interupt. i tried grounding the interupt wire, not grounding it. eq/norm switched those. i think i tried every combination. i have a feeling if i just buy the ainet/rca cable it is not going to work. this was my ex's HU and he had the ipod thing all hooked up with the 420i, before he pulled it it worked fine. are there any wires in the harness that are needed for the ainet to work? maybe when he wired it up when and soldered all the wires he left something out because i didnt have a cd changer