Only the second time I have used the smoker. I am extremely confused. Digital thermometer laying next to brisket is reading 230-240, but the built in thermometer on top left of the smoker is reading close to 400. Smoking on Oklahoma joe offset smoker. I thought it would be reversed and the grill grate temp would be higher. Paola's are burning steady and oak logs are producing a nice little flame. I really hope it's cooking 230-240 and not 400. Thanks!