Lexus GS430 User Manual page 313

D If a Mark Levinson brand audio system is installed:
G22066
Automatic sound levelizer (ASL):
When the audio sound becomes difficult to be heard due to
road noise, wind noise, etc. during driving, touch the "ASL"
switch. The system adjusts to the optimum volume and tone
quality according to the noise level.
When the system is on, the sound adjustment level is
displayed on the screen.
SURROUND:
If you touch "SURROUND", surround sound will be enabled.
(d) Your radio antenna
The wire antenna is mounted inside the rear window.
NOTICE
D When cleaning the inside of the rear window, be
careful not to scratch or damage the wire antenna.
D Putting a film (especially a conductive or metallic
film) on the rear window may affect the reception of
radio or mobile telephone. For the installation of the
film, consult with your Lexus dealer.
(e) Your cassette player
When you insert a cassette, the exposed tape should be to the
right.
NOTICE
Never try to disassemble or oil any part of the cassette
player. Do not insert anything other than cassette tapes
into the slot.
AUDIO
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