With the latest Oculus Software 1.10 Oculus introduced a new feature called “Asynchronous Spacewarp” which is always enabled and meant to enhance the experience with frame rates below 90fps.
There can be situations where Asynchronous Spacewarp introduces quite heavy judder (more precise: randomly inserted wrong frames a few times per second) with the current vorpX version. If you experience this, please enable “Fluid Sync” on the display page of the vorpX ingame menu. Doing that reliably fixes the issue.
The conditions that can lead to this are already known, a hotfix that addresses it without you having to enable Fluid Sync will be made available next week.