I actually ditched the 997 for a 983 tri-top for this very reason. The tri-top still did it a bit, but then I moved down a binder size and it doesn't happen at all and it binds a ton better. The tightness of the smaller size stretches out pretty quickly.
Curiously, I thought i would prefer the 997 to the tri-top because I wanted to be able to pull it down securely, but I found the opposite is actually true - the 983 stays in place far better than the binder part of the 997, at least in my experience.