Compatibility of SRM files

Hello,

I just switched from a RetroArch install on a machine with LibreElec to a RetroArch install on an Amazon Fire TV. I had to update some of my N64 roms, because they were not recognized on the new install (No-Intro requirement).

I also copied a savegame as SRM file into the games folder of the new install. Filenames of rom and savegame match. Unfortunately, the savegame is always overwritten with an empty savegame when I start the game.

This issue was also mentioned in this quite old thread:

The suggestion was to fix the SRM file by padding or truncating it to correct size. My file was slightly smaller than the new empty savegame, so I tried adding some FF bytes. This did not work, the savegame still gets overwritten.

Does anyone have another suggestion? Maybe the changed rom is an issue here. Is there any checksum in the SRM file that I have to update?