My Quad Castile insert is leaking smoke around vent pipe attached to the stove. The gasket that is supposed to seal the stove to the vent pipe adapter is relatively new, but has never sealed right from day 1. I used some Rutland sealant on both sides of the gasket last year which helped, but of course I have to break that seal each time I do a proper cleaning of the vent pipe. Does anyone else have to use sealant on the stove or should the gasket be enough?