I have had no problems with my prefold CDs but recently saw some tiny black spots. Now that i realize it must be mildew I am freaking out. The other day i put them through two hot washes with a half cup of vinegar. Today i did another vinegar wash then ahot wash with 1/4 cup vinegar. The stains are still there! I won't know if i have really killed the mildew unless the stains are bleached. What should i do!!!