[BFV] fps drops/1 second freezing/weird sensitivity changing(?)

[Flanelman]

Hey guys, I haven't played BFV in about 2 months and I'm really struggling to play now. I'm getting constant FPS drops and freezing for ~1 second. A related issue is that I usually play with BFV set to "high priority" through task manager which usually sorts all this out for me, and it still does, kind of..
 

When I set the game to run in high priority I get what I can only describe as "inconsistant sensitivity".. so pretty much half the time I have my normal sensitivity and half the time I have a slower, or much slower sensitivity when running in high priority (so impossible to run or aim properly), If I run in "above normal priority" my sensitivity feels fine but I get the before mentioned fps drops and freezes. Anyone have any idea what's wrong?
 

Temps are fine, and 2 months ago I played 60fps perfectly fine on high priority and I've since slightly overclocked my GPU (tested before and after OC and no difference.) I cleaned my fans and replaced my thermal paste on both my GPU and CPU today and still having the same issues.
 

Specs:
GTX 970M
i7 4720hq
16 gb ram
1tb 7200rpm

Speccy temps:
CPU: ~70
GPU: ~50

Thanks in advance!

[191x7]

Install an SSD in that laptop and run the game from it. 

As for the sensitivity - play with the "Uniform soldier aiming" turned ON.