Brace height sound variation

Every year or two I decide to tune my brace height and go through the whole shoot/listen/add a few twists/repeat scenario. Occasionally some high or low value causes a bit of a rattle, but other than that I've never really noticed a difference in sound as I go through the full range in increments of a few mm. Every tuning guide, video, and forum post makes it sound like there's one (or two) obvious sweet spots where everything is noticeably quieter, but embarassingly I've never noticed this...

Brace height sound variation