Lately I've been having problems regulating the temps on my large. I smoked a butt this past weekend and was trying to keep the temp @ 225. Everything started out pretty good but the temperature started creeping up slowly. I have the lower vent cracked open ~ 1/8" or less and have tried with and without the daisy wheel. I have a good seal with my gasket. I have a PartyQ and it does the same thing with it installed. At first I thought the PartyQ was screwed up, but when I went back to the old tried and true method the same thing happens. Anyone have any pointers?