Re: OxyClean + Vinegar -----> WOWSA!!
Just did the experiment with some inserts and whatnot recently rec'd on FSOT, just to give them a fresh start. Nothing had huge stink but some faint remnants of 'eau du pee', lol!!! Took pics, so I'll upload soon. It was really foamy but no big reaction. I put in what I had left of my vinegar (maybe 3 cups or so) and a scoop of original oxy... then emptied a boiling tea kettle over it and topped it off from the hose.
The dipes look really new and white. They're in the washer now so I'll update when they're done.
I do think oxy foams slightly in warm water (not like this though), but some of the suds you're seeing are probably from it's natural oxygen properties. I do love the stuff for red (rust, blood, wine) stains, though!!