Hi all, installed a Serenity two months ago, so far it has been awesome. Heats my home well now that I have it dialed in. Just this last week I started getting a loud clunk/knock from the auger, happens about every 12-15 cycles. Definitely coming from the motor side of the auger. I checked to make sure the shaft set screw was secure and all the motor mounts were secure. What else should I be looking at? Thanks in advance.