Hey kids... Just a question. For a few days now my Castille has developed(only on low setting as far as I can tell) a slight whistle, sounds worse at night with sound carrying(and the thirty dogs hanging out outside lol). Its not ground halting screaching but like a low whistle. Sounds almost like someone blowing lightly into a coke bottle. So.....I cleaned off the exhaust fan(which wasnt dirty hardly at all) I traced the sound to what I thought was at the convection blower....cleaned that all up nice...wasnt to dirty but a lil dust on the blades. But....now I'm thinking....hmm....when I'm listening and following the direction of the whistling....sounds like the whistling "may" be coming from one of the airflow holes in the burn pot....maybe something in one of the holes causing a slight whistle maybe? Havent checked that yet......any ideas?