Hyper Key functions "recursively" even if "Prevent Recursive Triggers" is selected

The hyper key triggers multiple times (between 10 and 19 in my count) making it unusable as a trigger for a Keyboard Maestro macro .

I have a KM Macro that I want to trigger with ⌃⇧⌥⌘V
The keyboard shortcut is not used anywhere.
One of the results is that it will paste the contents of the clipboard in the textfile I'm editing (the other is that it will trigger the Hook.app)

If I use the trigger with all modifier keys (e.g. DON'T USE the Hyper Key), then it works perfectly, and I have ONE copy of the clipboard in my textfile.

If I use the BTT Hyper Key (which is mapped to CAPS LOCK), then I end up with 10 to 19 copies of the clipboard, one after the other.

So I deduce that the Hyper Key mapping is not working properly (since the macro itself is working when triggered "manually")

I've tried activating the "prevent recursive triggers" condition, to no avail.
Have made sure Karabiner Elements (my old Hyper Key trigger) is uninstalled and inactive
Restarted device,
Deleted and recoded the trigger

None of these work.

Device information:

  • Type of Mac: MacBook Pro 15inches 2016
  • macOS version: Big Sur 11.3.1
  • BetterTouchTool version: 3.563