I got on here to see if I could get help with the same problem and happened to see this thread. We record on a JVC GY-HM100U PROHD with SD cards. Every so often there will be one clip in a batch of clips I import that does not load a thumbnail and no video program understands. This happens even though the .MOV extension is there and the file size is fine.
If anyone wants to give a shot at fixing one of the clips, you can get a ~50 mb one here: https://www.megaupload.com/?d=BH289G93
Not sure what else to try. So far I’ve tried VLC media player, MPEG streamclip, FinalCut Pro, Windows programs, and compressing/uncompressing the file.
Managing Editor of The Bright Side, a Michigan TV show.
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