Hello Peter,
Sorry for your woes.
The only other thing I can think of is a freshly formatted card.
I ran into a similar situation a few years ago and was told that I should reformat the SD card before each shoot. Also, there are counterfeit SD cards on the market. If the prices seems too good to be true, it might be counterfeit.
Regards,
Ty Ford
Cow Audio Forum Leader
PS: Oh, Audacity opens raw audio files. I wonder if you tried that. I was sent some files to see if I cold open them several years ago from a Google employee. He recorded meetings on his cell phone so he didn’t have to take notes. In THAT case, Audacity could see the files. You problem is different, but at this point why not try. Audacity is a free download.
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