Are we agreed that #156
is what we're talking about?
Now that I've heard a sample I can hear that from my MJ-1 tenkeyless w/ Browns if I put my ear to it. From pretty much every key I'd say. But I had to hear the example first to really pick it out.
To me that suggests that the noise is there from the Cherry switches, probably on all of them, but it is picked up and/or accentuated differently by some kind of assembly difference on individual boards.