As prior reported to the admins with the X-Station

I also can now confirm that it must have to do with not cleanly booting the game like it's meant to be with a original disc.

https://github.com/JonathanDotCel/unirom8_bootdisc_and_firmware_for_ps1/issues/3

I suggest you guys begin documenting stuff like that. Your Xboxes and all the newer stuff will eventually also stop working, but those are harder or even quite impossible to fix. At least harder than putting a drive emulator in the PS1 or Saturn.