[title] Remove the knob from the control with the problem
[* black] Remove the control knob of the switch you are having a problem with. This one had a problem with the volume control specifically.
[* icon_reminder] If the unit has never been repaired, this may take a moderate amount of force. Do not force it, but don't be afraid to use some pressure if you have to. Units that have never had a knob fall off will be harder then ones that have to remove.