I disabled the beta and the problem went away
For people with this problem, I switched to using my Rift S with the SteamVR Open XR and the flashing has gone.
I gave up using SteamVR at first because of the strange pin barrel distortion, but that seems to have been fixed now. It all works quite well.
Same here with Quest 2. Audio stuttering as well.
Same here, after the Oculus update today msfs vr with Rift S has become unplayable, constant white flashes
Tried VR today with my Quest 2 for the first time in a few weeks. Annoying strobing flashes are effecting things for me too so gave up.
This works, Rob. I opted out of the beta, downloaded and re-installed Oculus, and now NO FLASHING AT ALL! Thanks to CodeLoran69
Hi folks, I have found that the white flashing is linked to TAA setting. I’ve been testing @TonyTazer1504’s settings thread with TAA at 60 or 80, and I have white flashing all the time, it’s horrible. Then I’ve jumped it up to 100 and the flashing drops right back, still happens every few minutes but not continuously.
I’m now going to deselect the Oculus Beta Participation option, then uninstall the Oculus App and redownload as per @ExpiredSpy56910’s suggestion, seems that’s solving it for most people.
Try what I just did. All flashing immediately gone and on top of that, I am getting unbelievable frame rates, now.
Oooooooh you’ve got me all excited now!
didnt work for me 
I see oculus just did ANOTHER update on top of the one from yesterday 
New oculus Link home I see (I’m quest 2)
before it was just a grey grid to infinity, now i’m in some mountain lodge…
Just loading FS, lets see
OK people, I THINK there are TWO separate white flash issues going on here..
first one are smaller, more frequent white flashes going across the windscreen of my Cessna 152,
i assumed these were something to do with refresh rates / resolution and my propeller ( i still do) i think this is what Flobud is talking about..and he might well be right 
but theres a SECOND white flash issue that covers everything, im even getting it in the menu before i actually set up a flight..
so far, for me, nothing has worked, i opted out of oculus beta, tried steam OpenXR etc etc all to no avail..
the search continues..
I had the same issue, uncheck the beta opt in option in the oculus settings and last version of the oculus software will be installed, then do the non beta update, and all works perfectly again. It appears you no longer need to opt into the beta program to run MSFS2020, and the non beta software is all ok performance wise.
Quest (1) user here, having the same issues. Lots of white flashes and sound glitches, though FPS seems to be a bit better.
Reinstall of Oculus PC App, having deselected the Beta before uninstalling using add/remove programs, has solved it.
By solved, i mean I still get the white flashes but only as often as i did before yesterday’s update (I’ll have a couple within a few minutes and then go 10-20 mins without any)
Framerate is unchanged for me.
Has anyone tried the later update that Oculus have apparently very recently released?
yep, updated 5 mins ago, didnt fix it
well at least we are not alone 