When I use the remote to lock the car doors, the rear passenager door lock makes a LOUD buzzing noise and the latch sometimes does not move. It also sometimes makes the noise when opening the doors using the remote. Compared to the normal click as the doors lock, the buzzing is loud. 2002 2.4Lt 4cyc Sonata 172,000 miles (all mine!, apart from 28 miles when I got it.) Anyone had this fault? Thanks in Advance:) Bryan