I went to play a video and it came up with an error and wouldn't play. I looked at my SD card in settings and it showed space used and free space. My music would not play either. I tried to unmount and re mount the card but it would not unmount. I turned the phone off then back on and it all worked. What caused this? And why? I also noticed that all my contact specific ringtones were changed to MP3 songs from my SD card that are not even listed as ringtones?? ETA... I just installed a 32GB SD card 24 hrs. ago.