I have more powder in unopened canisters of different lots that I’ll use. I’ve only loaded with the two powders and always empty the hopper and trickler after loading. Obviously I’d like to isolate the cause, but honestly feel like I’ve checked everything I can. I’m not sure what other variables other than the particular lot of powder or the brass I used can be changed. As I said initially, it’s quite disconcerting, but I’m not sure there’s anything left to verify.