I have a 30 mes that is a 1500 watt model, that I got 2011 and only started using it in 2013. I sure was missing out! So I have noticed lately that the longer it's on I have to keep turning down the temp knob. Today I burnt my almonds bad well black on the bottom rack. started at 210° and when I checked an hour later it was 270°. So I adjusted it back to 215°and again it went back up to 270°. OK by the time I finished I had the knob all most turn to the Lowest setting. In the past I had to adjust but very little one only once in a 3 hour smoke.
What is causing this? How to fix it? I don't want to babysit it constantly.
I did let it warn up 45 minutes. Outside temperature was 40°