I am having a weird issue with a Lopi Revere insert. Once the wood is burning at a good rate (getting the second burn) I push in the intake control - not all the way and the bypass is pushed in. After an hour or so from pushing in the intake control we smell smoke in the house. I have noticed over that period of an hour the fire is reduced to a small flame and the result is somewhat like rolling flashes of fire. Almost like the smoke is super heated and igniting in an explosive manor. Could this be causing some sort of back draft or negative air pressure forcing a burst of smoke out the intake or where the stove pipe connects to the stove? Some additional info...this has happened only a handful of times this year, bought this stove 6 years ago and have never experienced this (why now?), the door gasket was replaced this year by a Lopi dealer and the chimney and stove are cleaned yearly. Any insight or thoughts on this is extremely appreciative.