Glitchy player rotation when connected to server

If someone could explain why this is happening, and assist me in fixing it I would be very grateful.

When pressing A, S, or D the player enters a very glitchy/jerky movement. Moving forward is fine, so I believe this is to do with the controller rotation yaw setting.

This does not happen when the server is off.

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Related question: Jittering character when rotating it - Character & Animation - Epic Developer Community Forums