Rinse aid light came on, I topped up reservoir but noticed that rinse aid then leaked out and ran down inside of door (i.e. into main tub). Appears to be coming from joint between dispenser and appliance door, not from the seal on the door of the dispenser. If I dismantle to inspect dispenser, is it repairable? (I am time-served maintenance engineer; no issues with dismantling/fettling).