Troubleshooting audio problems with mixing board?
Physically, you can check out the following:
Power cable to mixer
Output from mixer
Input connector
LR, ST button on routing to main fader(on some mixers only)
gain up on channel(top knob on mixer, aka trim)
No compressor or outboard gear limiting the signal
Is the input functioning? Try plugging a mic in and see if you
can get that to work
Is the amplifier on?
Dumb Stuff:
Mute buttons
Faders up?
If there is a more technical problem, consult the manual and
online forums for the particular product.