I installed an aftermarket Android headunit in 09 Mazda 6. The headunit powers on and works. The problem is no sound, I saw some videos and connected the wires (B)amp to (B/W)power ant. The sound worked momentarily, then nothing. I spliced in to the 12v socket to (B)amp wire, radio worked momentarily, then it blew a fuse and no sound. Headunit still works but no sound. How can I get the factory amplifier(black box under pass. seat) to turn on when the radio turns on? Any ideas or wiring diagrams would be much appreciated, thanks.