Hello, I've been having an issue with HDR on my setup since last year that has yet to be fixed, and I haven't seen much of anything online that is similar to the issue I'm having.
The issue is my monitor when HDR is enabled is dimmer than it should be, regardless of what the SDR/HDR Brightness slider setting is. I can only get it back up to the correct brightness if I boot up a game that is native HDR, then the entire desktop will be at the correct brightness. That is until the monitor has to turn off, whether that be when opening a fullscreen game, adjusting any monitor setting that causes the monitor to turn off momentarily or restarting/shutting down my PC. This exact behavior has been the case since I first got this monitor last year, and it behaved exactly the same with both a 5600 XT and a VEGA 56 through both DisplayPort and HDMI connections. I tested this monitor with a RTX 3080 with DisplayPort and HDMI and this issue was not present, so I'm sure it's not a problem with the monitor itself, but I don't have another HDR monitor to test my AMD cards on to see if this combination is just an odd case.
Any suggestions and help would be greatly appreciated!