Lexus 2004 GX470 Owner's Manual page 294

To adjust the volume of the headphones, turn the knob.
Turn right to increase the volume. Turn left to decrease the
volume.
The maximum volume depends on the type of headphones.
NOTICE
The headphone input jack lid must be closed before you
fold up the second seat.
With some headphone generally available in the market, it may
be difficult to catch sound properly. Lexus recommends the
use of Lexus genuine headphone.
Please contact your Lexus dealer for further details.
Wireless headphone: You can also enjoy the rear seat audio
system with a wireless headphone. For details, ask your Lexus
dealer.
CAUTION
Adjust the volume when you connect the headphones
to the jack. Loud sounds may have a significant impact
on the human body.
Finish
AUDIO
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