IOS: how to prevent the storyboard editor from automatically moving my stuff?

Sometimes I have a layout that works fine, but as soon as I open it in the storyboard editor in xcode, it automatically performs a bunch of changes that break my layout.

I can literally start from a clean branch, open up my storyboard in xcode, and without touching anything, dumps a bunch of changes to my XML storyboards.

Why does it do this and how can I prevent it?