RE: Aack! Major stink issues
Stink usually comes from one of a small number of places:
Too much detergent
Too little detergent
Change in diet/output
Since you say it's not buildup (I haven't used SG/washing soda myself so can't say whether this could build up), then perhaps they are not getting clean and need some extra oomph (more detergent, a little bleach, Calgon water softener - an extra wash cycle with no detergent won't help clean them, but will help rinse out extra detergent). Or has your DD's diet changed recently - introduction of solids, perhaps? This can make pee more potent and make the dipes stinkier.
Single mom to
DS ("twice exceptional") - September 2002
DS - February 2006
DD - July 2009
DD - July 2009