App freezes when turning passthrough off at runtime

Hi, I've gotten the new passthrough API in Unity to work in my app.  I have it turning on at the start, but I'd like to turn it off programmatically later.  I tried setting the isInsightPassthroughEnabled property to false on OVRManager, but my app freezes when I do this.  No clues were printed to the logs when the freeze happens...  Is this a known issue?  Has anyone else been able to get passthrough turning on and off at runtime?  thanks!