Hi everyone! I'm new to the forums, so please forgive me if this question has been answered already (after searching, I don't think it has though

).
My girlfriend has a 2005 Camry SE that she just got back from the Toyota body shop here in town after getting some hail damage fixed. Her car has the nice JBL sound system with 6-disc in-dash CD changer. When we got it back we noticed that the rear speakers are now very quiet, you have to turn the volume way up to even get a bit of bass out of them (like to volume setting 45 or so). The front speakers sound fine however, and when we've got the Fade set to R2 (2 levels more sound to the rear) lke we usually listen to the stereo, you only hear sound coming from the front speakers and barely any from the rear.
The gentleman we talked to at Toyota told us that they wouldn't have done anything with the speakers or stereo, but I find that hard to believe because they had to drop the headliner inside (I'm not sure what that entails) and they also had to fix hail damage on the trunk lid (there was hail damage to the hood, roof, and trunk and it was all removed using the Paintless Dent Removal technique). The rear speakers definitely did not sound like this when we brought the car in.
So, my question is does anyone know anything about the speaker wiring in these cars and what they might have unhooked/connect incorrectly/etc.? The way the rear speakers sounded before, I would imagine that there is a small amp somewhere in addition to the amp in the head unit, but that's just a guess. Any help/advice would be greatly appreciated.
Thanks!
Scott