Just wanted to share something I just found out about eARC and Dolby Atmos. So I've been connecting my Xbox One X directly to the TV, and have the TV send audio to the AV amplifier via eARC. The setup works for sure, but I occasionally get audio cut offs which I always thought was a bug on the TV.
But I was reading online about similar user experiences. There was no exact setup like mine (Samsung Q80T, Xbox One X and Yamaha RX-V685) but the issue is just like how I encountered it. There were some people who said if they disable Dolby Atmos output on the TV, the issue goes away. But of course you just get lossy Dolby Digital audio.
Someone else thought about the issue. Could it be that the Atmos track bandwidth is too big to send over eARC? So he changed his HDMI cable to a HDMI 2.1 cable, and the issue went away. So I also changed the cable from the Xbox One X to the TV to a HDMI 2.1 cable. The audio drop out issue no longer happens now.
Previously the cable from the Xbox was the one that came with the Xbox One X. Meaning it was a HDMI 2.0 cable, not HDMI 2.1. The cable from the TV to the amplifier however is HDMI 2.1. If I plug the original cable directly to my amplifier, the audio output is fine. It only happens over eARC.
Could it be that the end to end connectivity between components has to match? Meaning any components taking part in the audio/video path needs to use the same type of cable ie HDMI 2.1?
Err correct me if I'm wrong but isn't it a common knowledge that e-arc needs hdmi 2.1 cable? Especially if want to use Dolby Atmos.