When we use an ultrasonic humidifier we are getting a white film on everything, wipes up easy with a damp cloth. It’s not ash because if we dust everything and don’t use the humidifier then no white film. We’re on a well with fairly soft water, no idea of the minerals in the water. I suggested to my wife we try the steam humidifier and see if it’s related to ultrasonic humidifier. Any thoughts?