Dolby Atmos audio delay with eArc

After a lot of test, to solve it i plug xbox on my lg cx with option sync AV arc bypass and activate earc with my denon 1600h.

If earc is off there is a big audio delay but my denon receive an atmos emulated (pcm) for all game, If earc on no delay atmos OK on halo, forza etc... But no atmos on ubisoft game same as farcry 6.

Ubisoft game not really atmos but a dolby 7.1 sound ?

My conclusion If xbox use dolby atmos emulation or no earc there is a delay, if earc activate no delay but only atmos with game compatible

Thanks for your reply, but that has obviously not resolved the issue.

I've done a few tests regarding the apps.

When the CX has eARC on and Digital Sound out set to passthrough and Allow Passthrough setting is ticked on the XSX, the sound bar is not recognised as an atmos capable device, but Netflix, Disney+, blu-ray player and the Dolby Access app all send atmos signal to the soundbar with no noticeable delay. No atmos sound in the XSX menu or in games is able to be played only the other sound format (not DTS-X though).

When the CX has eARC turned off and digital sound out set to passthrough the XSX recognises the soundbar as a Dolby Atmos capable device. The soundbar then receives atmos audio, however delays are now introduced in everthing mentioned above apart from the Dolby Atmos app. The sound delay in this situation, seems not as bad as when the the CX has digital sound out set to auto.

When the CX has eARC turned on and digital sound out set to auto the XSX recognises the soundbar as a Dolby Atmos capable device, however everything has a delay introduced. Strangely Netflix and the bluray app seemed the least affected, but the Dolby Access app and Disney+ it was quite noticeable and in games it was worst.

Thanks for the response. That’s along the lines of what I was thinking (the xbox not needing to support eARC). This would mean the current issue I am experiencing is caused by my TV not properly passing through the audio of the Xbox.

From what I’ve seen, the higher bandwidth of eARC is required to pass through full, uncompressed Dolby Atmos with no A/V sync issues. I am currently having an issue where the audio from the Xbox is lagging behind the video whenever I play a game with Dolby
Atmos enabled. Ex: I fire a shot in Call of Duty and the sound has a delay. Just wondering if its my TV having a software issue or if its the Xbox.

My current console setup is:

Xbox plugged directly into my TV (2019 LG C9 OLED, which supports eARC and Dolby Atmos). All of the ports on the TV support HDMI 2.1 features (eARC, ALLM, VRR/FreeSync, etc...)

I have my sound bar (Sony Z9F, which also supports eARC and Dolby Atmos) plugged directly into the TV.

The Xbox and sound bar are both connected to the TV via Ultra High Speed HDMI cables that support eARC.

Hello AnchelLabena,

We appreciate you for bringing this up to Xbox Forum.

We are sorry to hear that you’re experiencing audio delay when using Dolby Atmos for Home Cinema on your Xbox Series X with LG OLED C2 TV and Samsung Q950T Dolby Atmos soundbar.

We've found similar issues with LG OLED and LG Atmos soundbar (with rear speakers) and used an earc extractor (4k Dolby Atmos compatible) which completely solved the problem. You pass the audio HDMI earc out from the TV through the extractor and into the HDMI in of your sound bar.

Another user, states having delays using the Xbox Series X with Dolby Atmos games and apps such as Youtube and Gears 5 but NOT from the Dolby Atmos app’s demos. The Xbox is connected directly to their LG BX TV via the HDMI 2.1 and using eARC > ARC on their Onkyo TX-NR656. The TV’s apps do not cause this delay using Atmos, and the Dolby App on the Xbox.

We also found an explanation from another that the delay exists because natively, surround audio from a gaming console is in LPCM. To output a bit streaming format (or in this case a proprietary PCM codec like DOLBY MAT 2.0) it has to re-encode the audio real-time which introduces delay. And keep in mind ONLY a very select few games are in Atmos.

It's good to know that connecting the Series X directly to the soundbar works just fine and Atmos content will play as intended with no delay. However, this causes a loss in other features such as VRR, 120 Hz and more due to the soundbar not supporting all HDMI 2.1 features.

We understand that you want to do the setup with the console connected directly to the TV, as should be intended. We hope that the information we provided is helpful.

If you have any other questions or concerns, please let us know.

We will be glad to follow up and help you.

Sincerely,



Moderator

Microsoft Community

Hello AnchelLabena,

We appreciate you for bringing this up to Xbox Forum.

We are sorry to hear that you’re experiencing audio delay when using Dolby Atmos for Home Cinema on your Xbox Series X with LG OLED C2 TV and Samsung Q950T Dolby Atmos soundbar.

We've found similar issues with LG OLED and LG Atmos soundbar (with rear speakers) and used an earc extractor (4k Dolby Atmos compatible) which completely solved the problem. You pass the audio HDMI earc out from the TV through the extractor and into the HDMI in of your sound bar.

Another user, states having delays using the Xbox Series X with Dolby Atmos games and apps such as Youtube and Gears 5 but NOT from the Dolby Atmos app’s demos. The Xbox is connected directly to their LG BX TV via the HDMI 2.1 and using eARC > ARC on their Onkyo TX-NR656. The TV’s apps do not cause this delay using Atmos, and the Dolby App on the Xbox.

We also found an explanation from another that the delay exists because natively, surround audio from a gaming console is in LPCM. To output a bit streaming format (or in this case a proprietary PCM codec like DOLBY MAT 2.0) it has to re-encode the audio real-time which introduces delay. And keep in mind ONLY a very select few games are in Atmos.

It's good to know that connecting the Series X directly to the soundbar works just fine and Atmos content will play as intended with no delay. However, this causes a loss in other features such as VRR, 120 Hz and more due to the soundbar not supporting all HDMI 2.1 features.

We understand that you want to do the setup with the console connected directly to the TV, as should be intended. We hope that the information we provided is helpful.

If you have any other questions or concerns, please let us know.

We will be glad to follow up and help you.

Sincerely,

Geri M.

Moderator

Microsoft Community

Thanks for your answer, Geri. For me, even the UI of the Xbox dashboard has the same audio delay. Youtube videos and streaming apps like Netflix and HBO Max also have it. In games it's even more noticeable since, well, the audio doesn't react with your button presses (e.g. jumping in a game and hearing the jump sound 300 ms later).

I'm still quite curious as to why an eARC audio extractor is the solution here. I would have imagined that the TV already extracts the audio and sends just that over to the soundbar without having to do any processing, since it's using passthrough. I'll consider the option as I try a few other things first (bought online new HDMI cables certified for HDMI 2.1 48 Gbps, in case one of the HDMI cables in my chain of devices is causing bandwidth issues), but it's still an odd one. I do see online lots of people have found that to be the best solution however, so there's hope that as a last resort, buying even more devices to connect may be able to fix it

Regarding the native surround audio of the console being in LPCM, it does make sense that encoding to DOLBY MAT 2.0 would take some additional delay for non-Atmos content. But if that was the case, then connecting the Xbox directly to the soundbar would show the same delay, which doesn't seem to be the case. At this point I'm not sure anymore if this is an Xbox issue, an LG issue or a Samsung issue, but with this problem being widespread with people having all sort of brands and devices, it sounds more like some weird Dolby Atmos implementation on a number of devices.