hi i have notice a creaking noise when towing especially loud coming up to roundabouts and in bumpy ground ect a local dealer suggested cleaning the hitch alko red handle that i have done but still creaking ,,what i did do was when i reversed my caravan into my drive ,,the next morning when i tried to pull away it seem to be jammed ,,but when i gave it a little bit of power it released any ideas what it could be from my explanation thanks