have you tried change the washer? try change the washer first but my guest is the the bushing on that handle is undersized. If that the case unfortunately you need to have new bushing and then tune it
I have the same one. The tap I had was from the brass spacers moving the tiniest bit. I put a single layer of Teflon tape between the spacer and the scales and trimmed the excess off. Rock solid now after many drops. No tap or play at all. I've never had to tighten it since I got it.
