OREI 4K HDMI ARC/EARC AUDIO EXTRACTOR. The HDA-929 4K HDMI ARC/eARC Audio Adapter is capable to output Dolby Atmos audio from an external HDMI source to eARC/ARC sound systems. It also provides a dedicated HDMI output port for outputing audio only when connecting with legacy AVR without eARC/ARC function.