Since a wav-file contains not only audio data but also metadata, could it be that the metadata gets updated in the DAW, but that Tascam now no longer recognises it/can’t handle it, if you just copy it back to the Tascam? Shouldn’t this kind of action instead be carried out by importing the wav-file back into the Tascam instead of just copying it back onto the SD-card?
If for instance you have three audio files in the Tascam and there’s metadata added and handled by Tascam keeping track of these files, then it would be logical to assume that if you copy file#2 into a DAW, manipulate it and then try to copy the file back into the Tascam it would now no longer ”fit”?
But if you instead import the file back into the Tascam the metadata for these files get updated and makes room for the new version of the file.
One shouldn’t forget that there are many different versions of wav-files out there. The ”normal” old type, the RF64 type, broadcast wav and so on.
If a wav file is put into a DAW from a SD card and manipulated, this file has to be saved back to the card before we can take the card back to the Tascam again. So does the DAW save the file to something the Tascam recognises and accepts?
The above scenarios is something I see daily in my work with audio books where publisher send all sorts of strange wav files - but then again - I might be completely wrong in my assumptions here.