Washable breast pads reek!

I use washable organic cotton breast pads and usually let them soak immediately after I remove them and before I wash them so they don't get stinky/mildewy but I recently went thru a big move and totally started slacking on that. Now they stink horrendously even after I washed them and I don't know what to do. Should I toss them or is there a natural way to remove the smell? Should I soak them in vinegar and baking soda? Do you think that would work?

Thanks!