See also:

Adjusting the position of and opening and closing the air outlets
Front center outlets 1. Direct air flow to the left or right, up or down 2. Turn the knob to open or close the vent Front side outlets 1. Direct air flow to the left or right, up or down 2. T ...

Electrical system
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Adjusting sound quality and volume balance
Press the “TUNE/SEL” knob to enter iPod menu mode. Pressing the “TUNE/SEL” knob changes sound modes.  - About iPod • Apple is not responsible for the operation of this device o ...