I have a 2000 blazer with factory bose system, only two of the six speakers work (door speakers only), also when I try to fade from front to rear the sound goes off, does this sound like an amp problem or radio problem. i would appreciate and welcome any help. Thanks so much!

My 2000 blazer sits slightly lower on the right side viewing it from the rear, can I raise the right side up a little by adjusting the torsion bar on the right side and if so which way do you turn the bolt to raise the vehicle on the right side. Thanks