How to Flash with MacOS 11(Big Sur)-Checksum Error

Hey … it doesn’t seem like we have much more to add. Things really seem to be pointing to something physical going on with the cards. Maybe try a different brand, just for grins? Try a different type of image (not RPI OS I mean… it wasn’t super clear from the history if you had already tried that). If you get a chance to update the status it would be interesting to know what happened from your last test.