I dont know why, but I lost the rear channel. No voice or music. It acted as a subwoffer. The system was installed in my Civic Ex with the factory amp 2 years ago without a problem. So I pulled the radio to start trouble shoot the rear channel. My speakers were fine. I put the front channel to drive the rear deck with no problems. I noticed that I was getting the same signal response as my subwoffer outputs. Very wierd. Anyway all my wiring was fine. So I did the reset on the radio, which is that pin hole on the front of the radio. And all is back to normal. Very happy with this unit.