12' accent GLS 4dr speakers
 

I have a base GLS sedan w/ auto trans and an OEM stereo.
The front speakers seem to be working just fine and are plenty loud. However when the fader is put on full rear, the volume is almost undiscernable. If memory serves, my car is suppose to have a 6 speaker system, yet nothing or very little seems to be coming out of the rear.
The fader and balance controls work. The rear speakers are equivalent to headphones compared to the front speakers.

Is this a common thing? anyone else have this same issue?
I was planning on replacing my speakers anyway, I guess its just the more reason why to.