Try SoftBums ~ esp Echos, trim/narrow of crotch & no rise snaps. I had this issue with my now 16 mo. It solved our problem completely. I was sad because our stash was all BG before, lol. I had to restash EVERYTHING. I also had some prefolds & wool soakers for backup incase it got bad.
Jodie ~ mama to Big K, Medium K & Lil' k