I think the monitor's behavior is somehow controlled by Windows and maybe it changed with Windows' latest updates:
2024-03 Cumulative Update Preview for Windows 11 Version 23H2 for x64-based Systems (KB5035942)
2024-03 Cumulative Update Preview for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2 for x64 (KB5036035)
I hope they solve this soon, because it's quite annoying to try to set the desired SmartImage settings and then the system resets them after a couple of seconds.