Sony GRAND WEGA KDF-55XS955 Operating Instructions Manual page 50

You can use the LCD Projection TV's DIGITAL AUDIO (OPTICAL) OUT
jack to connect a digital audio device that is PCM/Dolby digital compatible,
such as an audio amplifier.
Using an optical audio cable, connect the device's OPTICAL IN jack to the
LCD projection TV's DIGITAL AUDIO (OPTICAL) OUT jack.
The DIGITAL AUDIO
(OPTICAL) OUT jack is
available only when a
digital IV channel is
received.
Optical audio cable
(not supplied)
• iiii ......
OPTICAL
50