I recently started noticing my washer would leave these little brown flakes on my clothing after a wash. It wasn’t a lot, just a flake here or there on clothes and it’s most noticeable on my whites obviously. I can clean them off with a paper towel. The thing is I wouldn’t see any buildup inside the tub but whenever I start a wash and let the empty water churn, I’d see the flakes in the water. So it would seem this stuff builds up in another layer underneath the tub. (My washer is a top-loading washer by the way).