i un hooked my 2 rear coax. speakers in the back of my jeep and when i turned the car on and listened, like it was all good and stuff and it was only comin out of the front speakers and then it all of a sudden faded out alot and when down in volume. when i went to the back of my car, there was vocals coming out of my 2 CVR's and it was actin like a reg. coax. speaker... is this ok? just want to make sure.