I recently upgraded to Big Sur. Since then, I'm experiencing an intermittent bug where triggers repeat even after pressing a different key.
For example: Let's say I press F11 to turn volume down. Then I press F8 to pause music. Instead of pausing music, volume gets turned down again. If I press F8 again, the F11 trigger gets triggered again. This will keep happening until I switch the current application (from Safari to Finder, for example). Note that I can't use Command+Tab in this situation to switch apps because that will trigger volume down instead of switching apps.
I'm running the latest version of BTT on a late 2014 Mac Mini with an Apple bluetooth keyboard (the kind that takes 2 AA rechargeable batteries). I updated to the latest BTT alpha release to see if that solved it. It didn't. I also tried installing the Process Priority Helper Tool to see if that solved it. It didn't.
I think I'm only seeing this issue with keyboard keys assigned in BTT as triggers, but that's just a guess. I haven't noticed it with my trackpad, for example.
I think I'm only seeing this with keys that trigger Applescripts? Just a guess.
EDIT: I may have gotten rid of this error by changing the applescripts the keys were triggering. I had my volume keys set to show an exact number instead of using the Apple volume graphic. The Applescripts included a 4 second delay before hiding the number. Getting rid of that delay may have solved the issue.