Turn off the volume

[bashirbr]

In the old version you can't change the volume, but in the new version you just have to open the settings panel within the game, in advanced mode you can change the video, audio, graphics and other things.

@edit

Just a quick rehash of what I said. You can adjust the audio volume in the old version, but it's not as effective as in the new version. This is also available in the game options (keyboard O).