[Ed Kolis]

To turn off the ding, copy the contents of the SE4\sounds directory (including the SE4\sounds\new directory) into the SE4\highliner\sounds directory - what's happening is the game's looking for the sound files in the mod directory (because a sounds directory exists under the mod directory) but it can't find them so it uses the windows default ding. Maybe if there's another SE4 patch the game will look in the default directory too, like with pictures...