Mouse X/Y event axis values stop updating once my game's window gains focus unless a mouse button is held down

Unreal Engine Programming & Scripting
, ,
#1

Both my InputAxis and default mouse input events stop updating their axis once the game gains focus. They start updating once I hold a mouse button down. Consume input is unchecked.

Input mappings: http://i.imgur.com/wCgHL6k.png

Video of it happening.