welp, i used to have a 9815, all you should have to do is switch aux-input on in the HU's settings... but you've tried that so im gonna have to go with its a wiring issue or a bad unit. you seem determined to wire this thing up yourself w/o buying the inexpensive plug from alpine; my suggestion would be to buy the KCA-121B from a local store like tweeter for testing purposes only. plug this in and hook up an aux source to it (i.e. your ipod) if your getting sound from it then you know you got your wires wrong. if not... id look into sending your alpine out for repair. Out of curiosity, do you have anything else plugged into the ai-net (like sirius or xm)?
link to crutchfield.com (
kca-121b) $15.99
as far as the switch on the side of your unit for the ai-net eq. on/off, this switch will disable the alpine from controlling the sound levels going to your speakers; you will have to turn up and down the volume using the ipod instead of the knob on your head-unit... so leave it on b/c that can be a pain in the ***.