So, just purchased a fast eddy 240 and loved it for the first 2 weeks. Last cook, came in to find a THICK white sour-smelling smoke coming out of the chimney. Opened the burnbox and pellets poured out of the door. 5 briskets, 4 shoulders later...oh well, stuff happens. Clear out burnpot and box, unplug and reset smoker for tonights cook. Starts fine, running a good temp and nice clean smoke. Come back 4 hours later to check on the smoker, and same thing happened. Can anyone help?