Stuttering when starting walking or sprinting

When attempting to initiate walking or sprinting, avatar will stop and start ("stuttering") in the direction I am trying to move, cycling between moving in the direction I am trying to go, and remaining still (mostly just standing still, with very little movement). Will generally persist for as long as 10 seconds, followed by normal running/ walking until I choose to stop moving. Once I attempt to move again, the stuttering continues. The issue will persist even after restarting/ reopening the game. This happens even when frame rate is above 130/ 140. Currently experiencing this in single player mode.