[FIXED]Weird mouse acceleration-like/lag-like skipping

So, once I started up a game i got into the intro cinematic. Then, when the train sequence commenced, I looked around a bit and then noticed that I got this very odd mouse lag. I’ve tried looking up over the internet, everything I found was not helpful for me.
I tried:
limiting fps to around 58
m_customaccel 0, 1, 1.5 and 2
reinstalling my mouse drivers
restarting my pc
putting in these launch commands: -useforcedmparms -noforcemaccel -noforcemspd
turning v-sync and mouse smoothing on and off
lowering graphical settings
changing sensitivity
sellecting all cores except one in task menager

However, none of those “fixes” worked.
NOTE: during some moments, my mouse sensitivity would either raise or lower, it’s pretty random. And the skipping often came when I turned right with my mouse (even though it could skip every now and then). I also think it might be a problem with raw input, however I can’t enable it, there’s no command for it)

GPU: AMD Sapphire R9 270X Dual-X
CPU: AMD FX 4300 Quad-core 3.80 GHz
RAM: 2x4 GB (8GB)
Windows 8.1 64-bit operating system.

I FIXED IT: I only had to download the Patch for Windows 8.1 called KB2908279 (it’s made for problems like these)

Thank you for updating the thread and posting the fix. Hopefully this can help others.

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