When I spool up the Gauss rifle now, it often gets stuck in fire mode; and there's no way to remove it -- that and I move like I'm encumbered. TAB does nothing and I can't even exit my Power Armor. Even a reload of the game doesn't fix the bug. It ensures you have to reload a previous save. It's happen to me twice now, so I can reproduce problem. It only seems to happen when the gun is used with the spool-up and not the insta-fire.
Image of it is http://i.imgur.com/gJj3IzG.png.