Important Concept to Understand:

The mixer sits between the inputs and the speakers/monitors (outputs). All connections should show an understanding of this concept.

Important Items from the Manual:

Meters (page 9) --- 'AVG' (average) LEDs indicate normal output; 'PK' (Peak) indicate overload.

Mic Power (page 9) --- press this button when using condenser microphones.

Wild Guesses:

Calibrate the mixer's peak level against the "red" levels of the computer's level meters (software). I generated a sound that peaks at -6dB and adjusted levels on the mixer to "almost" go into the red when this sound is playing.

Use the Pre-Amp knobs before resorting to volume knobs: keep volume at zero.

Unwanted Noise:

So far I am very pleased with this tool. The only time I heard it hum was when I set the Power Pack (AC Adapter) too close to the main console. So now I try to keep the Power Pack away from the main console.