Optimus 120-2113 - Manual (Page 12)

Hold down POWER for about 3 seconds to change the display's color from
amber to green (or vice versa).
Adjusting The Controls
When you listen to your stereo, you can adjust the following controls to
suit your listening preferences.
/\ and \/ - Repeatedly press to increase or decrease the volume. VOL: and
the volume level appears on the display (such as VOL: 30). The
volume level ranges from 0 to 40.
WARNING: To protect your hearing, do not listen at high volume levels.
Slowly increase the volume to a comfortable listening level.
The display automatically returns to the time display 5 seconds after you
finish adjusting the sound.
AUDIO - Repeatedly press until BAS, TRE, BAL, or FAD and the current level
appear on the display, then repeatedly press /\ or \/ within 5
seconds to change the stereo's bass, treble, balance, or fader
settings.
Notes: When you adjust the balance toward the left speakers, L and the
left balance level appear on the display (such as L 5). When you
adjust the balance toward the right speakers, R and the right
balance level appear on the display (such as R 3).
When you adjust the fader toward the front speakers, F and the
front fader level appear on the display (such as F 5). When you
adjust the fader toward the rear speakers, R and the rear fader
level appear on the display such as R 3).
If BAS, TRE, BAL, or FAD and the number disappear before you press
/\ or \/, repeatedly press AUDIO until the setting you want
reappears, then repeatedly press /\ or \/ to set it.
MUTE - Press to temporarily silence the stereo. - - - - appears on the
display. To restore the sound, press MUTE again.
LOUD - Press to boost the high and low frequencies when listening at low
volume levels. LOUD appears on the display. Press LOUD again to
return to normal sound.
Radio Operation