- From the desktop, right-click the volume icon (located in the upper-right corner) and select Open Volume Control. The Volume Control window is displayed.
- In the Volume Control window, select Edit > Preferences. The Volume Control preferences window is displayed.
- Click Master Mono to add the track to the Volume Control window then click Close.
- Enable Master Mono by clicking the volume icon (the red X will disappear to indicate that it is active).
- Try playing a soundfile and adjust the volume to determine whether or not the control works.
- Select File > Quit to close Volume Control.
- At this point, you may realize that the desktop volume icon is not controling the sound output. To configure this, right-click the volume icon again and select Preferences.
- Select Master Mono then click Close.