https://learn.microsoft.com/en-us/troubleshoot/windows-server/remote/frame-rate-limited-to-30-fps
On RDP Server, Open up Registry Editor as administrator
Go to
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\WinStations
Add a new DWORD
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Set the name to DWMFRAMEINTERVAL
Set the Value to 15, and base Decimal.
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Apply and reboot.
You may also want to look at enabling the following options in Group Policy Editor
Computer Configuration > Policies > Administrative Template > Windows Components > Remote Desktop Session Host > Connections > Select RDP transport Protocols > Use both TCP and UDP
Computer Configuration > Policies > Administrative Template > Windows Components > Remote Desktop Session Host > Connections > Remote Session Environment > Use hardware graphics adapters for all Rmote Desktop Services sessions
https://github.com/maxprehl/TurboRemoteFX
https://www.reddit.com/r/sysadmin/comments/fv7d12/pushing_remote_fx_to_its_limits/