My 4 Channel Amplifier CA-AM40700/CA-AM41200 Has Only 2 Channels Working.

This could be happening if you have selected '4 channel' on the input selection switch but have only 2 channels connected. The input selector must be set to the correct position. If '2 channel' is selected (with 2 channels connected) the output is supplied to all 4 output channels and if 4 channels are connected but 2 channels are selected you will only get 2 output channels. For more information contact us at Product Support