Panasonic TH-24L400H Operating Instructions Manual page 7

Ω
Use HDMI 2 to connect to an extension with ARC(Audio
return channel) capability the sound.
Enjoy the sound of external devices in multichannel sound
(e.g. Dolby digital) 5.1CH), connect the device to the
loudspeaker. For connections, see the device and the
instructions for the loudspeaker.
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