Hm.? I checked the pot, and it looks fine - but for good measure, I reflowed all three connections.? Didn't fix the problem.
However, I've discovered that when I key down, the clicking goes away, and I hear a tone.? On key up, the clicking is back.
It doesn't go away when I switch to Peak BPF - but its character does change, and in Peak BPF turning the cap does affect the sound a bit.
Curious.