I have a 2020 Traverse RS with the 10 speaker Bose System. For some reason, there seams to be little to no sound coming out of the rear speakers. Is this normal? The front speakers work fine, but the rear are quiet and muffled. The kids are always asking us to turn it up, but it makes it really loud up front to do so. When I use the fader, the rear has very little sound. Just curious if this is normal. Thanks.