Unplayable mouse stutter/sluggishness ingame

I was hoping that the new update would have fixed this but I'm still having the issue. Basically in game my mouse acts incredibly jerky, stuttery and/or sluggish as if it is missing mouse polls for a split second or something. This does not happen in any other game or program nor does it happen in the menu of Apex, just in play. It also does not happen while looting, just when aiming and looking around. This has persisted from the 1.2 Update and was not fixed in the Season 2 update. Sometimes it also feels like my keyboard controls lag too, in the sense that ill release the W key and my character won't stop/slowdown for a split second.

Another clue is that my Teamspeak 3 client begins to have severe inbound packet loss at the same time as the jerky mouse so all my friends sound incredibly robotic, which suggests something perhaps CPU related?? I dont know.

Things I have tried:
Turning off Origin overlay
Turning off Nvidia overlay and Shadowplay
Closing the Nvidia thing in the system tray
Uninstalling the Steel Series mouse software
Closing Teamspeak 3
Reducing mouse polling rate from 1000hz to 500hz
Increasing mouse DPI and reducing in game sensitivity (i play low sense)
Unplugging and replugging mouse into different USB
Uninstalling and reinstalling drivers inc mouse driver
Swapping between windowed/borderless window and fullscreen

Changing various graphics options such as all the v-sync options and no v-sync

I have no controller plugged in, but funny enough it works fine using controller (pc controller main incoming)

Changing CPU priority of the application

Repairing the Apex install in Origin

Capping the FPS via launch command

Closing just about everything I can in the background

Tabbing in and out of the application

Restarting etc

PC temps are normal

Unplugging non vital peripherals

Changing my DNS

My Specs:

Processor: Intel Core i5-6600k @ 4.40GHz

Memory: 2x 8GB @ 3200MHz

Motherboard: ASRock Z170 Gaming K4

GPU: NVIDIA GeForce GTX 1070

Harddrive: Samsung SSD 860 EVO 500GB with 340GB free space

OS: Windows 10 Home

Mouse: Steelseries Rival 110

Running a ASUS 144hz 24" Monitor and a second 60hz Monitor