Huh. Tried a clean install and it works from the SD card, but not from the Flash drive. Well, that's good to know. Thanks for the help.

If by trying several cores you mean try the other provided emulators, then yes. If you didn't mean that, then no because I don't know what that means.

I just grabbed a redump .cue/.bin from someplace and it's still doing the same thing. I suppose the next thing to try would be to reinstall Recalbox.

Though, would it potentially be problematic that I'm running the games off a flash drive instead of on the SD card the system is on?

The bios looks fine. And I tried both the SegaCD and the PCEngine CD with .cue files instead of .chd, and those didn't work either, so I don't think it's the files or the bios. Well, it might be the files, but not the file types. So I'm at a complete loss here now.

@Scavy What do I look for in the bios?

@DacK I do not know what that means, so probably not.

I did switch the emulator over to Genesis Plus GX, and it didn't do anything. Is there something in a config file I need to change to make it work, or is it just being weird?

Using RecalBox on Raspberry Pi 4, and all the games for SegaCD and PCEngine that are .CHD will go to the loading screen, then kicked back to the game selection screen. Any way to fix this?