One thing I've generally never liked in games is the 'select' sound that is used, and in wargames you click on a lot of units throughout a game. The sound can get annoying, but if you turn off sounds entirely, you miss some of the great sounds that do exist in the game.
So I created a short, silent click MP3 file. Just backup your original file and install this one and you can keep all sounds on, without the endless clicking sound!