iphone 4/4s calls are not going to the car speakers. It was working fine when I was using a 3.5mm pin wire from the headphone Jack to radio aux input. I decided to simplify by getting something that can handle both functions with one connection from iphon-charger and phone calls. The wire i got has a 30 pin connector at one end and branches out to two wires;one wire is a USB and other is a 3.5mm pin. It routes music to car speakers fine but wont route phone calls. Is that an iphone limitaiton or a wiring limitation? It really sucks because I was hoping to have just one wire coming out of iphone instead of two like I had before.