I think that the smoke goes to those areas of least resistance that are closest to the fire pot. I think that the hopper lid being unsealed, allows for the updraft. If there was some way to correct that, it might stop that. I have ordered a 1070 and will look into that. As long as this does not cause hopper fires it may not be a problem. ??Pretty consistently I see white smoke coming from my hopper when shutting the grill down. Anyone else seeing this with the 1070? This is with Costco pellets, wondering if that might be a problem?