Ethernet Over HDMI is used by newer AV receivers to support eARC (extended audio return channel). The older ARC spec would work with any HDMI cable, but bandwidth limitations only allowed compressed 5.1 surround sound. eARC uses the higher bandwidth from Ethernet Over HDMI, allowing uncompressed 7.1 surround and Dolby Atomos streams.

(If you're not familiar with ARC/eARC, this lets the TV send audio from its native inputs back to the AV receiver over an HDMI cable. Without ARC, you need to plug everything directly into the AV receiver.)

eARC is neat in theory, but my experience with it has been that’s too unreliable and unstable to actually use in practice.

I even bought new cables to make sure there wouldn’t be issues, but eARC audio regularly falls out in ways other sources (including regular ARC) doesn’t. And when it fails there’s literally zero tools for diagnosing it either.

Maybe around the time of eARC2 we’ll have something working as well as Bluetooth does today. (Yes, that’s me being snarky)

I've had good luck with eARC without any intermittent issues. Of course, I'm only using it because my tv has two EDIDs, one that allows 4K video for my streaming box, and one that allows audio for my Blu-Ray player. So I have the streaming player connected directly to the TV and audio over eARC to the reciever instead of going through the reciever. I was pleasantly surprised that this works fine, but not surprised that it doesn't work for everyone.

I’ve had no problems with eARC when used together with my Appletv and LG C1 TV - which I’m happy about because the appletv does not offer any other wired audio ports.

That's unfortunate. I've been hoping to simplify my HT setup and eARC was something I wanted to target in an upgrade

> The older ARC spec would work with any HDMI cable, but bandwidth limitations only allowed compressed 5.1 surround sound.

My 2012 Denon AVR-1913 won't do ARC with just any HDMI cable. According to the manual it must be an HDMI with ethernet cable and experiment has shown that the manual is correct.

actually, if i understand correctly, earc doesn't use HEC. it just re-purposes hec wiring for something useful

It uses the same pins, but it doesn't actually use Ethernet. I'm pretty sure it's IEC 60958/61937, like SPDIF.

I went down this rabbit hole the other night and found a German Blu-ray receiver T+A K8[0] from 2012 that supports the HDMI Ethernet Channel. I have not found, however, the other piece of equipment that I can only suspect may be be some sort of HDMI IP injector.

[0](https://www.homecinemachoice.com/content/ta-k8-blu-ray-recei...)

> Ethernet switch: distribution of an Ethernet uplink connection to BluRayplayer, streaming client, TV monitor and up to 3 source devices (via HEC),up to 2 more external devices via LAN cable (e.g. playing console

from the manual

My understanding is that Ethernet over HDMI is still used by consumer devices, just no longer for the original dream of switching wired internet given the modern ubiquity of WiFi. More recent standards such as ARC [Audio Relay Channel; used for a number of surround sound setups] and CEC [Consumer Electronics Control; used for passing remote/controller data between devices] both piggy back on the Ethernet pins, and I believe they entirely interfere with using the Ethernet pins as Ethernet (though maybe only in the available bandwidth/speed?).

I tried to use this once in a theatre to connect a camera watching the stage to a greenroom backstage. It worked sometimes, but was super unreliable. Latency was often several hundred milliseconds, and sometimes the image would just straight up disappear. It may be that we had bad HDMI<->Ethernet devices, but that’s the thing: It’s not a “works or doesn’t” kind of thing, it’s a “varies with the quality of all the devices in the chain” kind of thing.

Those HDMI-over-Ethernet devices have very little to do with Ethernet-over-HDMI.

Unless you really boosted the gain, they could really only do about 30m reliably. What you wanted to buy is HDMI-to-HDSDI and HDSDI-to-HDMI converters, which could do much longer over RG59 (and much longer over fiber).