Hello, I have been using our Snow Flame 2100 corn stove since 2001. I noticed a small amount smoke rising from the corn hopper when refilling a couple years ago. It seems to be getting worse. I can see and smell the smoke rising when hopper lid is open. I'm wondering if over time, the auger has worn and allowing smoke to seep around it. Or is there a seal that may have gone bad? What should I be looking for? Thank you!