Getting the boat ready and I found a weird issue. The aerator switches seem to be malfunctioning. There is an auto/off/manual switch and a min-max knob. When I first rotate the knob from off, nothing happens, but once I hit auto or manual on the other switch, and then go back to off, the pumps stay on until the knob is turned back to off. Any ideas on what might be going on? Wiring issue or bad switch?

my guess is a bad ground on either the switch or knob. pull the wires to both and check where they go and all connections