Hello! I am a first time user (after seasoning of course) and I notice that my MB Cookmaster won't go higher than 150*. At first, I was using an extension cord, but subsequently read not to use an extension cord. I moved unit closer to the outlet, but the smoker still won't go over 150. I have the dial cranked up to High and it's been there for over 3 hours. Could there be a problem with the thermometer? I have minimal smoke coming out from the door seem (which I know is normal). I took a peak an hour ago and the pork is cooking nicely. I just don't want to over cook it if the thermometer is bad..... Suggestions?