I had same problem. Removed the cover for the lights and there is a screw holding a small cover with some wires going into it. After taking out the screw, rotate the cover down to expose the 2 wires powering the air flow blades. I disconnected one of these (the connectors are insulated) and this cut the power to the blades so now there is no more noise, but also no air flow. Not sure how much air flow there was as the blades turned very slowly anyway. Good luck.
pawprint9 at yahoo.com, June 2011