Occasionally, my sound device manager will tell me that a new device has been plugged in or unplugged, which will pop up a little window from my sound manager, causing me to have to alt-tab back into the game. Hover isn't necessarily the only program that does this on my computer, but it does seem to happen way more often on Hover (and no other game). Specifically, I know it's the program itself because it happens when I press an input. That is, if I hit space to jump, it might happen, or flicking the mouse wheel. Obviously, it's not just your game, but consider looking into anything that you happen to be doing with sound devices.