Turn on/off the eARC function: Switch to "ON" position, the AUDIO ONLY port will output the eARC/ ARC audio;Switch to "OFF" position, the AUDIO ONLY port will output the audio from HDMI IN port. EARC HDMI 2.0 Audio Extractor 4K 120Hz HDR 1 In 1 Out HDMI Splitter Audio Converter 4K HDMI To Optical TOSLINK SPDIF 7.1.
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