Horrible Sound From Amp....plz Help!!!

yeah....I hooked up the turn on lead to the radio's fuse on advice of a neighbor but i am getting only one side to work and the other makes an annoying crack/poping sound whenever i turn the car on....i have traced the problem with the one side to the input wires. I used speaker level input because im still using my factory h/u and i have checked power, ground, and speaker connections......is it possible that the input wire could be corrupted? it goes out on the good side if the wire wiggles too much.....