As a workaround I renamed a scph5552.bin to scph5502.bin and replaced the file in my bios directory. Now my games are booting correctly, but you should consider to adjust the issue in the mednafen psx cores.
bios for pal is actually a correct dump, this case must be related to some pal games having protection and what you have is actually a patched bios. i can only find one link, and that md5 states its a bad checksum.
This Manifesto is rooted in the work that, for several years now, some research organizations in the field of biosciences in Europe, Africa, and North and South America have been carrying out on issues concerning the relationship between scientific research and society by using the Responsible Research & Innovation (RRI) approach, initially through the STARBIOS2 project and, most recently, in the context of the ResBios project.
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