I recorded the lot numbers, and the times of purchases - and it was at least a few months in between, but my lot in January was so bad - I sent it back to my supplier. That one was obviously more than just light brown specks. It had obvious effects from a rodent issue in the packaging facility.
It just threw me for a loop when months later I get another bag from RD with the same problem. And yes, I tried switching to the RD brand, but the product quality isn't the same, so I prefer to stick with Dominoes. I am not too far from the Baltimore, MD processing plant, so I am very curious to see if this problem extends beyond my local area.