Whoa. Slow down, and start from scratch. Before you do ANYTHING, turn all the gains down to zero. Follow all the outputs to the correct speaker (FL, FR, RL, RR), and make sure you follow pollarity (very, very important). Make sure you have set your amp to play 4 channel stereo, and not 2 channel with a bridged third or something crazy like that. Then when you are sure all the wiring is good, turn the head unit up to about 1/4. Then slowly bring the gains on the amp up one channel at a time. When you come to a channel that has no audio, troubleshoot that channel the entire way..... from the headunit output to the amp input, then from the amp output to the speaker. Each channel should be done individually, and I'm sure you'll find your problem. If not, you may want to have a professional do it.