I have the same problem with a current pair of bindings and it’s the heal strap. It’s too cushioned, so I’m order to get a snug and responsive fit, I have to crank it down, which then pushes down on my arch too much. I’d either get a more firm/stuff boot, or buy different heal straps, or both. If you have Burton bindings, you can buy their current heel strap system for $20 each and should help prevent that issue.