Rainbow 6 sige mouse lag?

I'm having a problem, in short it is basically that the mouse sensitivity seems to be tied to the frame rate. This is what is causing the inconsistent mouse lag. I have a temporary fix of turning on vsync but if i drop down to 30 fps the mouse sensitivity gets cut in half. I find that ridiculous and i have never seen this happen in any other game i have ever played.

If you have any ideas on a more permanent fix you know works let me know. Because i cant test it anymore, I'm 2 minutes of game time from not being able to get a steam refund anymore. But with that said any speculation in regards to the problem will be appreciated.