I've got space on my usb drive/if I click on File Manager, it says I've got roughly 7GB (50%) space available on it. I'm trying to copy a video (.mkv) to the movie/hdd folder on a Mac using Finder so that I can watch it via. the box, however I receive an error message saying that it can't be copied because there isn't enough free space. Any ides why and how to resolve this?