I've got my 2 3/4# corned beef brisket in the smoker. The temp rose fairly steadily from the 50s to 153 where it held so long I took out the Mav 732 meat probe for a while. It dropped. I put it back in and now it's hanging up at 151 It's been in the low 150s for about an hour now. It went in almost exactly 4 hours ago. Is this why it takes so long to smoke one of these things? I'm shooting for 190.