87 Nova electrical problems

I dunno what the deal is. I had an awsome JVC cd player installed in my car about 4 years ago. All of a sudden, most likely from driving over large bumps and pot holes, it quit working. First it would cut out and there would be static. And I thought it was just the cd player. Well it was even happening to the radio. So I took it out nad installed a brand new cd player and the same thing is happening. The only catch is my factory radio is working fine. If anyone can help me with this please let me know. thanks