Did you try VLC Player to play the files?
Why I ask is most PCs can't play those files on the cards without a better player.
I want to find a new camcorder that uses an SD card. But I need to be able to use a card reader rather than hooking up the camcorder to a tv or computer to access my files. I have an old model Samsung that allows me to do that. But it is draining my batteries so it is time for a me one. I did buy a jvc last week and returned it to the store since the only way to play the videos was using the camera.