VR - Performance Impact by Screen Mirroring? Anyway to disable? (Odyssey+/WMR)

I just DL'ed Squadrons and really enjoy it so far on my Odyssey+. But I'm realizing that my monitor is also displaying the game while I'm in VR and it seems to be having a performance impact.

In fact, if I alt-tab or otherwise minimize the Squadrons app on my desktop screen (no Squadrons visible on my monitor), the in-headset video framerate and smoothness goes WAY UP and it's much more pleasurable in the headset. However, there's no sound! I then activated the "Play sound even when minimized" setting under Sounds which let's me play the game with sound, but then I'm having another issue (bug?) While I now I have sound and the high framerates in headset, with the app minimize, a lot of the HUD information either doesn't appear or update in the headset (distance to target, subtitles, when I hit Pause, it doesn't display the mission info, etc). Very odd...so basically I've been toggling in and out of the app (which requires me taking the headset off and on) to get mission info. Pretty annoying.

"Display VR View" is OFF in SteamVR.

Any one else encounter something like this or any other game? I thought when the regular monitor is displaying my VR view it shouldn't affect performance but it's night and day difference.

I have a high-refresh (200hz) main display and I noticed a bug report around that so maybe it's related?