You cant just plug the ipod into the USB port? on my mother in laws 2012 the head unit talks to her iphone through that USB port just fine. That said her head unit was swapped at the dealership for a pioneer with NAV. If your head unit doesn't talk through that USB port amazon sells extension 30 pin apple connectors, One side clips to your existing cable with a female end, and has a male side for connecting to your ipod on the other.
I know its not really the solution your looking for but they are very easy to use and extremely inexpensive
13 WRX Hatch - Cobb OTS Stage 1