Speakers Cutting out

I have a 05 H2 and I installed a AHP-6500DVD. About a month ago, I hit a railroad track and some of the speakers shut off. I turned the deck off then back on and it was fine. Now everytime I hit a bump, a different speaker shuts off. I replaced the factory amp thinking that was it. Its still doing it. WHat else can it be??

sounds like a short. Have you replaced the speakers? Something seems to be grounding out. Double check everything!