SteamVR Motion Smoothing - Check/Enable/Disable within UE4

Hello helpful UE4 VR devs!

I have a curious issue that is driving me nuts. I have a VR app that’s not running smooth in SteamVR.

However, it IS running at 90 fps, actually. If I disable motion smoothing within SteamVR, the framerates go up. Smooth as butter.

If motion smoothing is enabled, I’m down again to 45 and jittery/laggy image.

I’m running UE4 4.21.2

Any idea about what is going wrong here is muchly appreciated :slight_smile:

Are there any commands in UE4 to check whether motion smoothing is enabled?