I tried searching for this issue but couldn't find much on it.
Basically I have a standard sound set up in my S3 (non bose) and a concert 1 single CD head unit. The front speakers are working fine but the rear ones aren't. The sub in the boot is working but the rear speakers don't make any noise what so ever.
Has anyone heard of this before? Is there a control board in the sub which might be broken?