I have an iPhone 4 and have recently bought an AUX cable. It works fine but it's inconvenient to have to use my iPhone to change the songs, rewind, etc., especially while driving. Is there such an AUX cable that will let me control (play/pause, REW, FF, next/previous tracks, etc) my iPhone's music with my car's built-in stereo controls? It would also be a plus to be able to see the current song's info (title, artist, album, etc) in the car stereo display as well as turn shuffle (aka random) and repeat on and off with my car stereo controls but it is not absolutely necessary. If such a cable does not exist, please give me some suggestions/advice. I've already done some research and do not want any external remote or any type of dock with its own controls. I want to be able to use my car's BUILT-IN STEREO CONTROLS to control my iPhone's music.