From time to time my SD card will appear to kind of stop working. I noticed this when my ringtone would revert to a stock Verizon one or I wouldn't be able to see some of my photos, which are on this SD card. Although I can't see these in their respective areas (ringtone settings or gallery), I can still browse through the SD card in a file manager and see all of those files. So then I have to go into settings, unmount and re-mount it (the 16GB card). Have any of you had this issue?