Thanks… Didn’t know 280 had been released (still showing 277 in the Pimax downloads page).
Tried 280, still no joy. Clean install of PiTool and SteamVR. I was able to get DCS to work a single time, launching from within PiTool. But each subsequent time (including launching from desktop and PiTool) caused DCS to time out and then just load into 2D mode. Same for MSFS.
Installed 270 on top of 280 and things launch as intended. I start PiTool, it recognizes the HMD is connected and starts to track. Launch DCS and it automatically launches SteamVR and enters VR mode (same for MSFS).
Pimax 8K X, Firmware: 184.108.40.2069. Running nvidia 516.59. I’ll try upgrading to 516.94 later, but shouldn’t make a difference as 516.59 came out well after 280 was released. And it’s working right now, IF I roll back to 270.
Opening another ticket, because this is very obviously a PiMax (PiTool) issue.