If you change your playback device in windows (Windows 7 => right click on the sound icon => Playback device => Set another one as Default) it creates three different bugs:
- Sound of game is not played anymore, anywhere.
- If you set your previous Playback device as Default, the sound does not return to your speakers.
- When you change zone in game (use a scroll, travel to another planet and so on), client freezes after loading. You have to CTRL ALT DEL tu force quiting.
I tried 3 times, same thing each time.
Note that you can continue playing if you stay in the same world zone, it will only freeze game when you teleport.