Command & Conquer 1 (PAL-G) - running too fast when emulated

Hi ho.

I can not confirm if it is only the German version, but I assume that all PAL versions of the game are behaving the same. This is the only game where I encountered this issue with default emulator settings.

I have been trying quite a few emulators and cores, but the game always runs way too fast. I am used to how the game runs on real hardware (PS1), so I know it is running too fast when emulated. The speed differs a bit between the cores, but it is always too fast. The audio and FMVs play at the correct speed. It is just the gameplay that is sped up.

Apart from trying different cores / emulators, I tried limiting the framerate, but that did not really fix the issue.
Tested systems / emulators / cores:

• PCSXBOX (running on OG Xbox)
• DuckStation (running on Raspi 3)
• PCSXreARMed (running on Raspi 3)
• Swanstation (running on Raspi 3)
• Beetle (running on Windows PC)
• PCSXreARMed (running on Windows PC)
• PlayStation 3 (official Emulator by Sony)

I hope that our community has enough knowledge that we can resolve this issue.

It seems that I found the solution myself, just after posting above.

At least with PCSXreARMed, you can reduce the CPU clock speed of the emulated PSX. In RetroArch, the setting is located in core options -> system -> CPU clock. The default setting is 57. This must be changed to 38.
The game will still run with 50 fps.

Background: For some games, the CPU clock speed can be increased to 100 to increase FPS without impacting the speed of the gameplay (e.g., Warzone 2100, Soul Reaver). Other games will speed up if the CPU clock is increased (e.g., Tomb Raider IV).
But I never found a game that needs this setting to be lower that the default 57.