I recently noticed that if I set the kick pedal threshold to a value under 30, I automatically get this constant "frenetic super fast kick sound". Even the fastest drummer in the world couldn't play that fast

The problem seems to disappear as soon as I set the threshold to 30 or above.
But now that only 1 out of 3 kicks generates a signal (sometimes 5, sometimes 127 for the same strength!), I'm thinking maybe the problem is not "material" (foam getting old, or screen mesh head getting loose), but something more tricky that would generate symptoms like the ones I just mentioned.
Any help before I dismantle the whole thing?
