Hotpoint washing machine dispenser leak

Hi,

I’ve been out to a couple of Hotpoint washing machines, not too sure of the models but its the swivel open type dispenser versions that are leaking slowly down the front. They only seem to leak on the final rinse. I’ve tried all sorts to stop it, cleaned out the jet holes, conditioner section, turned the water pressure down and even tilted the machines back but it still seems to leak. The only one i’ve managed to stop, i had to turn the pressure down so low it took ages to wash and got a complaint.
I’ve got another to go to tomorrow, but without changing the whole dispenser and valves I don’t know what else I can do to stop it.
Most other makes, this is a very easy fix but i’m just wondering if anybody can shed any light on how they get over problem.

Cheers