Making the output from a car audio mono?

[oakesave]

I am profoundly deaf in one ear, so stereo is wasted on me. Also, I have to turn up the car audio loud, which can be discomforting to any passengers. Is there a way of pushing out the signal from a CDX-GT35U car audio so that it comes out mono? Then I can put all the signal into the speakers nearest to my good right ear louder than on the left hand speakers?

I know I could use an adaptor from my iPod using the aux input - but I then lose the iPod control features on the car audio unit. And that does not help with radio and CD outputs.

Thanks