Hi, Please can someone help, as we have a Tricity Bendix Si 340 freestanding cooker that in the last few weeks has had a habbit of the back left hob element heating up even if the knob on the front says its off. The rest of the cooker works fine just bit worrying haveing a element coming on whenever. does anyone know what could cause this? and how it could be fixed? not really in a financial position to start getting people out to look/ fix. so any help is welcome. Thanks.