Operating System Mixer
- GNU/Linux: Run the command 'alsamixer' in a terminal, press F6 to select the sound card, and press the up arrow on your keyboard to turn the slider labeled "PCM Front" all the way up.
- Windows: Click the speaker icon in the system tray. Click "Mixer" in the popup. In the mixer window that comes up, in the Device column, in the drop down menu between the top of the volume slider and the bottom of the icon at the top of the column, select the sound card. Click and drag the volume slider to its top.
- Mac OS X: Adjust the volume by clicking the speaker icon in the system tray.
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