Car Stereos: Rear Speaker Problems, rear speakers, zone controls

Question
I have a Kenwood KDC MP4028. When I play the tuner all speakers work just fine. When I play the CD or my Zune through the Aux my rear speakers don't work, just the sub and front speakers. Thanks.

Answer
Does your stereo have zone controls?  It sounds like maybe the cd and aux have been turned to dual zone control for one reason or another, and they just need to be switched back.  Check all of your radio's settings and you should find the problem.  Hope this helps, Scott