FYI, Shooting a commercial production, I've seen a fair amount of moire on lightly ribbed and smooth sweaters.
Not color but color and pattern moire, using the leica 120.
First I freaked, but in lightroom the moire tool worked magic and I really mean magic. I can't believe it could take moire bands out of a ribbed sweater without destroying detail, but it did.
I haven't seen it on 99.% of the project, but obviously if there is something slightly off, that's the image a client selects.
Bottom line it was a 5 minute fix (honestly) and I can't say it was the leica or the 120, I just think it was messing with the camera gods.
Anyway, the camera worked great, still does, no other issues, but make sure you learn the moire tool in lightroom because it's amazing.
IMO
BC