I have messed with that finger to no avail ( way more than I should have really, trying to get it set to work with very heavy thread) still just a slight rattle, nothing bad , but not silent either. I should really post some more video of it when I get the treadle noise under control.
oh at the noise is more like the finger is a tad anrrow or something, the whole hook assembly kinda clicks back and forth making the smallest of metalic "clicks" each time it contacts the finger.