Framerate changes mouse sensitivity, low fps = low sensitivity and vice versa

When framerate is low, mouse sensitivity is less than when framerate is high.

I play various other FPS games and this issue has only ever happened to me in Titanfall, Scyrim, Medal of Honor and now BFV.

First I thought the raw mouse input must not be working right. I tried turning it off ingame, but it just enabled mouse acceleration. As in slow moves = low sensitivity, quick move = high sensitivity.

Raw mouse input is on.

I replicate the issue by standing still and having my view first horizontal, causing my FPS to hover around 90-100. I then move my mouse across my whole mousepad and count how many degrees I turn. It was usually around 270°. I make sure the framerate stays around the same level throughout the turn and the result is very consistent.

I then look straight down at the ground, causing my FPS go jump up to around 150-160. When I now move my mouse across my whole mousepad, I turn a bit over 360°, consistently.

I was able to consistently do this. And as my frames occasionally dropped even lower in combat, close to 50, the sensitivity would be even lower.

Needless to say it is extremely difficult to be consistent with my aim when this happens during combat.

I have tried dabbling with future frame rendering 1-3, vsync is off always, no change.

In an empty map when I get a solid 120+ consistently, the mouse feels perfect. But when it drops low, the sensitivity drops as well.