2009 Impreza Steering wheel audio controls

[vortriede]

I installed an aftermarket stereo in my 2009 Impreza. It has input for steering wheel control, but my Impreza did not have the controls on the wheel. So, I bought a set of controls on eBay and installed them; however, there do not appear to be any wires coming to the area where the stereo is that communicate with the switches. The socket that the switch set (there are switches for both the cruse control and audio) plugs into has conductors for both sets of controls, the question is, where does the audio set go to and where can I pick it up to take it to the stereo? TIA for any pointers!