Performance issues recording/streaming OBS Studio

[Fleehisalt]

Hi. I'm having issues trying to record or stream CS:GO. Whenever I open the recording software, the game starts running extremely poorly. Strangely enough, I don't get a drop in FPS (the game still runs at a steady 300+ FPS) but moving and looking around turns it into a laggy and choppy mess. This happens even when I'm not recording or streaming but just have OBS open with CS:GO running. The resulting stream or recording runs perfectly smooth, but the game itself becomes borderline unplayable.

I doubt it has much to do with my PC's specs (i7 7700k, GTX 1080, 16GB of RAM) as I manage to stream and record all of my other games (some of which are more demanding than CS, such as BF1 or DOOM 2016 at high settings) without any of these effects. Playing and streaming CS:GO, I still have ample room/power to spare in my GPU, CPU and memory (none of which break 45% usage even when recording, streaming and playing simultaneously).

I have already tried to mess around with my OBS settings and turned my in-game graphics all the way down without any major effect. Google shows I'm not the only one with the problem, but none of the supposed quick fixes have done much for me. It does not happen with any of my other games and I'm dumbfounded as to why this is the case now. I normally wouldn't really care too much about one game not running properly, but I have only recently built my first PC and am now somewhat concerned about there being issues with my PC itself. Thanks for any advice.