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How much vinegar do you use?
I use the Downey ball fill with vinegar. Will automatically empty in rinse. I also have put fab in freezer for few days
This is a timely post! I recently got a bunch of fabric, and it all smelled "old." I washed it with Borax, and most of it came out fine. Some of it, however, had the bad smell "revive" when I ironed it. It was thinner fabric, and I wondered if it was perhaps a poly-cotton blend and that's what made the smell stay. The rest was fine, no smell at all.
I make sure I use color and perfume-free ALL and clorox 2 clear plus Oxy-clean in everything I wash and I have not had any problems. To me, using something like Fabreeze only 'masks' teh odor and does not get rid of it. Be sure and not use hot water or dry hot as you will 'set' odors and stains. Use cold.