This Kitchen Aid was my Christmas gift about 20 years ago. It’s the Professional model. I only use it about twice a year at Christmas and Easter for baking cookies, pies and cakes. But recently I have been using it quite often because of the pandemic. I have replaced the beater earlier because of chipping issues and started using the stainless steel which was great until recently I notice this gray stuff appearing in my cake batter and my cake when done has a dark swirl in it. I always had wash. Is this harmful? Can I get a replacement. Was there ever a recall on this product? Is it lead? Help....