Please choose a 4:3 resolution in all Source engine games to minimize the chance of any potential issue like this. There’s a notification missing about that in the current build. Also check the hint text regarding Direct VR in general that is shown during each scan, it’s there for a reason.
And last but not least please always make sure that your games are updated to the latest version in Steam before reporting any issues. Especially for Direct VR this can be very important.
I’m already on 4:3
“I tried this new profile “Portal 2 [vorpX] without optimization, 1600×1200”
4:3
640×480, 800×600, 1024×768, 1152×864, 1280×960, 1400×1050, 1600×1200, 1920×1440, 2048×1536
And i confirm no issue in Portal 2 : Mel,
just on portal 2 classic (both Steam versions) have this odd flicker every few seconds.