I've never experienced this from Merrell hiking boots before, but the plastic in back cracked and is coming off on the toe as well. At $140, i certainly wouldn't expect this, and Merrell has always been a premium boot. The inside still looks perfect and the "air cushioned" soles are still in great shape. I ordered another pair, thinking this was just an anomaly, but after reading some reviews it sounds like more the norm. All the pictures I've seen look just like my shoes, cracked in the back with the glue from the plastic sole coming loose from the shoe. Did you change the materials or outsource the manufacturing of your shoes? I'm hoping I'm not sorry i replaced them with Merrell instead of a different brand.