I have one of those virtual reality sound labs 200 watt 2 chanel amps from walmart for $50. Anyway, i have it all wired up........battery to ground, input and output. All im getting is a red light, and 4.4 volts coming through the unit. I know that the power cable has 12 volts coming through because i tested it.........everything has been tested, all to no avail. Any tips? I had it working for a while, then one amp shorted out, and now i have a new one.