The Audio Controllers let you control many RTGS3 parameters using the amplitude envelope of the incoming audio signal.
Clicking a gear icon opens an Audio Controller setup window:
"Source" menu = sets which audio input channel to use for detection.
Trim Amplitude = lets you adjust the gain of the audio input signal before detection.
Attack = sets the time duration in milliseconds over which interpolation (smoothing) is applied to an increase in the audio envelope.
Release = sets the time duration in milliseconds over which interpolation (smoothing) is applied to a decrease in the audio envelope.