Quartet's ABC touchpads are not responsive when I press them

The ABC Touchpads are completely assignable with no constraints. However, It is possible to assign them to functions that are not available. For example, if a touchpad is set to engage a particular speaker set, but the main output selection is set to Stereo, that particular touchpad would have no effect. To get back to the default Touchpad assignment you can Reset All of Quartets parameters to default by holding down the Large main knob while powering up the unit and keeping it held until the unit comes online.