Sony KDP-51WS550 Operating Instructions Manual page 96

Speaker
Audio Out
On Select to turn on the TV speakers.
Off Select to turn off the TV speakers and listen to
the TV's sound only through your external
audio _'stem speakers.
This option can be set only when the Speaker option is set
to Off.
Variable The TV's speakers are turned off, but the audio
output from your audio system can still be
controlled by the TV's remote conti_l.
Fixed The TV's speakers are turned off and the audio
output of the TV is fixed. Use your audio
receiver's remote control to adjust the volume
(and other audio settings) through your audio
s_tem.
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