I have been using my Kirby G2000 Limited a lot lately but I have a problem. My apartment is in an old house and the house is settling or has been settling and some of the surfaces are uneven because of this. My bedroom is the worse and I have been having a horrible time vacuuming the the carpet in this room. Certain parts of the room I can have the floor nozzle one notch before the lowest and it works fine. Other parts of the floor at the same level it stopps the roller brush and I almost burn up a belt. It I raise it up a level it goes to high and the brush isn't even touching the carpet. I have been vacuuming the room one half with the brush roll and the other half with the hose and floor brush. Any ideas?