Washer overflows by failing to stop water entering fabric softener dispenser. Also, washer stops on other cycles indiscriminately and makes a humming noise. Must be shut down for 5-10 minutes and then the timer is restarted to go again. These two issues happen maybe once every 20 loads, so not every time. But we must stand adjacent to the washer to see if overflowing.

Have checked: (1) pressure switch (it clicks open/shut with modest air pressure on all load levels); (2) pressure switch inlet hose...no visible holes or clogs, blows freely; (3) water valve inlet screens...all look ok, no grit or dirt on screens.

Suspect timer or solenoid on line leading to fabric softener dispenser? Other ideas appreciated. Where is the solenoid located? Thx much.