FPS Stuttering when moving with keyboard key

Since the last patch, when using a keyboard key to move the character, there is intense FPS stuttering. When using left/right click to move the character, the game runs perfectly smoothly.

For context, I usually use the W key to move around to avoid strain on my right hand. This stuttering is making the game unplayable.

Data
Moving with mouse:
Frame time - 7ms very stable
CPU - 5-11ms

Moving with keyboard key:
Frame time - 8-16ms frame time, stuttering very hard with FPS drops
CPU - 20-60ms

Moving the mouse around quickly while holding the keyboard key to move drastically spikes the stuttering and CPU/frame time.