Might as well face the truth and stop the whining in realizing NOT all cards conforming to industry standards implement the standard protocol in exactly the same manner with some memory card models/production runs not working reliably in all applications.
We know that deck manufacturers often list tested cards as OK for use in their machines for this reason. The cards they recommend should work OK, and sometimes even these cards get production changes making them not work reliably as predicted.
If we find multiple instances of a certain flash model not proving reliable at some point with new firmware, best NOT to continue using this card, tell the deck manufacturer, and wait for firmware fix before testing again.
It is not possible for any manufacturer to continually test/retest all models/newer production runs of flash memory, so it's up to us to find cards not working communicating the problem so another firmware correction is possible.
We can assume with each firmware update addressing specific models of flashcard compatibility involves the retesting all available flash models at hand to see if still working as before the upgrade, but important to realize not every card made, and not the latest production runs of all cards get firmware upgrade tested.
This means new firmware upgrades solving issues with more models of flash cards, may also make untested card models/recent production runs of previous user found OK models incompatible if these specific cards were not at hand for manufacturer's testing during each firmware upgrade.
Suggest testing all the cards you intend to use before committing for important purposes, and retesting with each firmware upgrade.