A: Instead of connecting the output(s) of an effect device to the AUX RETURN jacks, it should be connected to the line input(s) of unused channels. This would make the channel fader the auxiliary return master. The channel should be set up as if it were receiving any line input signal. This means setting the proper input trim level with the fader at unity and setting the pan control (stereo or mono). Next you would MUTE the channel, which would send the auxiliary returns out the ALT 3/4 Bus.