Sonos Beam lip sync issues through ARC - something to note

  • 26 July 2018
  • 4 replies
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Userlevel 4
I recently bought the Beam and frequently sharing anything worth noting or the problems I have encountered on this forum.

Another issue I have found with the Beam worth noting is the audio/video sync issues through HDMI ARC (out of all the interfaces!)

Optical works fine, but there's a flaw with some TV's passing Dolby Digital through HDMI ARC causing large (300-400ms) sync issues where the audio comes after the video. You'd think ARC fixes this... but it seems to have made things worse.

Essentially, some TV's struggle to decode video and pass DD5.1 through in sync. My Sony 43XE7073 has this issue, but it's common with some people who have this issue with flagship TV's too.

You'll find if you run audio in PCM or just stereo the issue is heavily remedied or gone. Something to do with the chip in modern TV's?

Anyway, I use my Xbox One S for media and am now (unfortunately) using the Optical out as my TV doesn't have an option to disable audio in conjunction with the Beam and using the remote raises the volume of both the Beam and the TV. So, again, disabled TV audio entirely and am using a separate audio output from the Xbox.

One thing to be aware of is that this has nothing to do with Sonos. If you have a TV that can pass DD flawlessly that's great. But there is a fundamental issue with some TV's at this time.

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4 replies

Userlevel 7
Badge +19
Hi, JackWright. Thank you for the information provided and for pointing out that at times, problems can be caused by an issue with products other than our own. It's not a matter of my being glad to shrug off the problem- it's a simple appreciation for instances where customers understand that our hands are tied, too. I'm sure this will provide clarity for many.

We are working with television manufacturers to alleviate issues of this nature- though as with many collaborative efforts, it's taking some time. Until then, the importance of having these discussions cannot be overstated.
Userlevel 4
Hi, JackWright. Thank you for the information provided and for pointing out that at times, problems can be caused by an issue with products other than our own. It's not a matter of my being glad to shrug off the problem- it's a simple appreciation for instances where customers understand that at times, our hands are tied, too. I'm sure this will provide clarity for many.

We are working with television manufacturers to alleviate issues of this nature- though as with many collaborative efforts, it's taking some time. Until then, the importance of having these discussions cannot be overstated.


That's the thing is that you'll get the same problem on other soundbars as well! Hoping Sony has a fix for their TVs. 🙂
I'm just wanted to add to the conversation to note that I am having the exact same with a TCL 49S405 49-Inch 4K Ultra TV and Sonos Beam connected via ARC HDMI. Have tried changing all the settings in audio for the TV: stereo, Dolby, Dolby + etc etc. Absolutely frustrating that I just purchased both of these products new and the ARC cross-talk is not working. Have tried router reset, unplugging, changing settings. All to no avail - the sound is already playing after the relevant video. As you describe above, the issue improves substantially - though not completely fixed - when put into the most basic stereo setting. But so frustrating that anything more than 2.1 setup is subject to substantial lip sync issues. Makes me wonder what the utility of the Beam is if it cannot deal with one of the most basic components of audio/video pairing!
Userlevel 2
Badge +1
Hi rpc,

Before you blame Beam, have you checked the TV settings?
Did you try to put your TV in cinema or game mode (this minimizes the TV's own processing, that may reduce delays throughout).

Why do you blame beam and not the TV? Beam doesn't introduce much delay itself (less than 30 msec, which is impreceptible to most people). So, if the TV delays sound in its digital output (e.g., due to dolby conversion), this is a problem with the TV.

What I hope sonos would implement is soundbar that I could plug my media sources into, and it would have an HDMI output (into the HDMI ARC TV input). At least for my setting, this would be superior. I use an Apple TV as my signal source of choice. I would love to output the best possible sound out of it, but the Apple implementation is that the best sound is in pcm and not Dolby (this is because of an HDMI ARC limitation, which cannot pass multichannel (above stereo) PCM ).
(I also would love it if Apple introduced airplay improvement for home theater applications, such as surrond sound over airplay and sound delay adjustment, but that's a long shot).