Sound just quits working

I've had this happen before, there is nothing that i do specifically that leads to this. All other sounds on my computer work fine, so it's not a speaker issue or a PC issue. But i'll be playing in game and then out of the blue the sound goes away. Sometimes i'll get random ambient/environment sounds but no battle sounds or music. Today i was in a dungeon, all was well, and then blip, no more game sound. My boyfriend behind me thought i muted the game, i was in mid battle when it happened. zero sound. typically rebooting the game fixes it, but as i was in a duty finder i could not log out. Would be nice if what ever is causing this had a resolution.