Patch for Vive Trackers support

I am having an issue where my Vive Trackers are sometimes rotating when I start UE4. Before I press the VR Preview button in Unreal I can see them in my headset in the correct position. However, once I press the VR Preview button to start the Unreal scene, some of the trackers rotate around to face the wrong way…and it is the actual orientation of the tracker, not just the display mesh. Any ideas to prevent this?

Thanks!