I haven't had this happen but have heard about it from someone else. I don't know it its plant bug or feed related. Flax seed and sunflower seeds are high in omegas any oily plant or seed would have it. Plus kitchen scraps could also add to it. Pam
I can add that ive also been told if they were stored near something with an odor theyll pick up the taste of that. I know someone in Utah who just had this happen.