my 300tdi 1995 disco drivers door when opening and closing actuator makes continous clicking noise like a machine gun. still locks and unlocks door, told by a mechanic that if changed need to reprogramme as it a master to all other doors, is this true, if so where do i get one and who reprog. or if not can antone advise where to get one. have taken door card off and tried to adjust but makes no diffrence.