I put a 4 - 5LB butt on the smoker last night at around 10:20. I've done larger butts and they have all taken around 12 hours to complete. This one was chugging right along until it hit 182. It began another stall, then the internal temp of the butt dropped a few degrees to 179. I was fine with that because I've seen it happen before. However, it kept dropping and right now, an hour and half later is is sitting at 171, where it has been for the past 30 minutes. I stuck another thermometer in it and got the same reading. Is this common? Like I said, I know about the stalls and even a temp drop a few degees, but 11 and showing no signs of going back up? I"m thinking about foiling, but I haven't been foiling and don't really want to do it. Any ideas?