I recently purchased a SanDisk micro sd card 64gb for my surface 2 mainly for videos. When I transfer videos to the card some work while others don't. They all work on my computer running windows 7 and are not protected files. I have reformatted the card multiple times and each time different videos work but never all of them. I also have an issue with videos and pictures randomly disappearing from the card. The videos play perfectly from my flash drive or off of the internal memory on the surface. Am I just dealing with a corrupt sd card or am I missing a fix? Any help would be appreciated. First time poster.