I am trying to transfer video from the jvc 4k to FCP X. To do this it needs to merge the four files from the four different sd cards. I'm trying to do this through jvc 4k clip manager, but every time I try to export the mp4 merged file, the software will tell me that it has failed trying to do it. Can you please give me some advice ? I've look for help all over the web, but it seems like if no one has encountered this problem before.