1, left and right car audio channel volume is not the same Troubleshooting: First check whether the host balance knob in the middle position, and then check the level of input and output level control knob is about the same, as well as left and right channel amplifier input sensitivity setting is the same, if still can not be excluded, can host signal line about swap, the smaller side of the speaker position will become larger, and if so, that the host has a problem, otherwise the problem after the segment. 2, a silent channel treble Troubleshooting: check crossover wiring is turned on, then the electricity meter from the crossover there is no end to measure sound, the speaker wire may be wrong input termination to the bass output. 3, noise Troubleshooting: Check rca signal negative end of the terminal is turned on, if rca signal output terminal of the negative side of the host has open circuit, the meter can be used to measure the negative terminal and the host chassis is turned on. 4, when the big, sometimes small volume Troubleshooting: first check the power ground contact with the shell of the car is loose, and then check the front and rear stages of the input and output rca is normal, and finally to see whether the normal sensitivity knob.