if it's only happening during the washer running - I suspect it's when the tub is being drained, right?
if so it's suctioning water out of your p-trap - if you have an auger or snake you might try cleaning out the standpipe where the drain hose goes - I don't think the other things are going to help - might just be too much hair and gook for the cleaners to fix.
@Pretzel we have tried so many things! Vinegar and baking soda, Draino, garbage disposal cleaner tablets, lemons and ice, etc. We called the maintenance guys (we rent this house) and they said there's nothing they can do because this house was built with cast iron pipes and "they just have that smell". 🙄
From the makers of award winning hallmark movies comes the next in a series of amazing biographies “fresh turds and broken dreams “. The story of a young women who…hahahaha
