I made a bad boo-boo.
Some of the slats in my WBS were getting loose, so, based on recommendations I heard here, I started boiling pans of water in the chamber to moisten the wood.
Unfortunately, had a brain-fart and I left the power on for a few days, with the smoker covered due to some rain that we got, so I've basically baked my barrel. I'm working to salvage it by applying water internally and externally - I'll let you know how it works out. Worst case, I'll use small screws to hold the slats to the hoops, but I don't want to do that if I can avoid it.
I'm also thinking about adding an indicator light to the heating element power circuit so that I don't do this again.