I just got finished cold smoking my 4th batch of bacon the other day. I've always had issues keeping the wood dust burning. I've tried filling the whole maze with dust. I've only filled it half way. This last time I only filled about 5"-6" and it kept burning for about 1.5 hours. When I filled up another 5"-6", it went out shortly after it got to the 2nd dose of wood dust. Any suggestions as to how to fill the maze smoker sand keep it burning by itself? Thsanks!