I have a 64 Gig Sd Card(Samsung Evo), it allows me to write files(movies, documents and music etc) successfully on the first 4 Gig and they will be working properly. However, on the remainder of the memory, it allows me to write any kind of files but the files become dysfunctional or even be disabled. For example, if I copy a song onto the remainder of the memory, the song becomes disabled(no longer works)