SD card problems although formatted as portable storage

Are all those cards from the same manufacturer? :thinking:

I wouldn’t suggest using a FAT32 formatted card with the FP4! I had some rather problematic issues ( :de: ) with files bigger than 4GB. Those shouldn’t be writable to FAT32 but the overlay filesystem makes this possible. Once the card is removed, that file will no longer be accessible and even putting the card back into the phone won’t make it recoverable again.