PC Game running but accepts no input

I have an intermittent bug where mid game I will lose all control of the game window. No input works - controller, keyboard or mouse - but the game is still running, like its stuck in the background i.e. window has lost focus). If I alt-tab out of the game enough times eventually I can usually get control of the window again but it takes about a minute - in many game modes that's more than long enough to get kicked for being idle.

If I get the bug it will happen again and again until I restart my system - but then might be fine for the next few days again.

I used to get this bug 2-3 times a week but haven't had it at all since I upgraded my system until tonight - when it happened twice in the same match.

No amount of searching the web has turned up anything useful. I haven't changed anything on my system in the last few days so I can't even point to having installed something new that's causing it.

I haven't experienced this issue on any other game or programme and I am at a complete loss. I have the game through EA direct.

Any suggestions, advice? Has anyone else had the same bug?