I found what might be a bug, clicking a combination of a couple buttons will make you auto run.
- Legacy ID
Jog forward and hold down middle mouse button then right click.
Also the way to stop it is to switch to your other weapon and it'll stop.
Affirmative. The auto run appears for me when he the weapon is holstered, standing and in the second stance. When he holding the weapon with the right arm only and freely moving the other. In some cases with that running stance the auto run can bug. A way to fix this is to do an action, like you said, or enter a vehicle etc..