This is a simple application which alternately mutes and un-mutes your system sound each time it's run.
If you pin it to your taskbar (its the speaker icon in the screenshot) you can run it with a single click.
Running the app without parameters toggles the mute / un-mute state, or it can be run with one of the following parameters:
- mute - mute the sound.
- unmute - un-mute the sound.
- volup - increase the volume.
- voldn - decrease the volume.