I am going to go with the fact that it is laundry soap. In the past I have had problems with this. For months I've been using Purex free & clear detergent, and the other day I had my husband pick up some laundry soap and he brought home just some regular Purex that is blue. Well, of course loads later when I go to pick out clothes I notice these horrible stains. Ooooh, it makes you so aggravated! I'm going to try the Vinegar and water solution to hopefully remove the stains. I think running an extra rinse cycle might help as well as not putting in as much detergent. I know I'm going to go back to the Purex free & clear and never look back.