I have a Hearthstone Santa Fe (no longer in the catalog) this is the third season, and the blower is making a cyclical noise (vibration?) when I use the rheostat to run it slowly. It didn't do this at first, and it is hard to hear when you turn the fan speed up higher, (but I think it is still there). It is driving my sound sensitive wife crazy, in turn which is then driving me crazy (know what I mean) the warrenty is only a year on the fan, and I'd like to avoid a service call. Is there a oil port for the fan bushings? Is there any service schematics that might help me figure it out? The Hearthstone website has nothing for trouble shooting or service info. Hoping that someone else had this problem and fixed it short of putting in a new fan. Love the stove, love the Skytech Remote I added, love the gas bill vs the wood bill, but need to fix the noise. Help!