I dont have the Mach system, but i DO have a premium system (factory amp). When i got the car, my friend who I bought it from sold his radio, but i planned on putting mine in cause its cooler anyway. I had to work so he did it while I was at work. I noticed tha the front driver, and rear passenger speaker didnt work. I figured he just didnt hook the wires right. Well I pulled everything put yesterday to hook up my amp and subs, and I re-spliced all the wires, and they still dont work. Anyone know what might be wrong?