FWIW, I still see lip sync delay with pass-through enabled. I have an LG C9 and Sonos Beam connected directly to the TV via the HDMI ARC port. 

I assume you are using the v04.70.05 firmware with your TV? See also the following...

I have the same TV (55” version) and not a single hint of a lip-sync issue here. I have the Beam connected over HDMI-ARC with two surrounds (no sub)… and I pass-through the following devices ..

• VirginMedia v6 Cable Box
• Apple TV 4th gen
• Sony PS 3

I also use the TV’s in-built Netflix, Amazon Movies, Now TV and Rakuten TV Apps.. and several others.

I have eARC disabled, I have not enabled HDMI Ultra HD Deep Colour, nor instant game response and my TV is setup using the ‘rtings' calibration settings, as mentioned within the LG forum, using the “Expert (Dark Room)” picture mode.

i know of at least two other Sonos users who have the 65” version of this TV and they have not mentioned that they are having lip-sync issues either.

All is working really well here, so I would suspect you either may have a hardware fault with one of your devices in the setup, an incorrect setting, or you perhaps may want to consider replacing one or more of your your HDMI cables.

LG Customer Support and Sonos Customer Care are perhaps also worth speaking to, if you are unable to resolve the matter. If it’s working for us, then it should be working for you.

Hope that assists.

Hi Everyone:  This is my first post and I really appreciate all of the suggestions.  I have tried to review the most recent tips for my issue.  I have the LG 2019 C9 65 inch purchased in June along with a Sonos Playbar, Sub and Two rear portable speakers. One HDMI cable and one optical. Internal TV speakers off.  I have set the pass through setting in Optical but still have lip sync issues it seems.  I have asked LG for input but they pass it off. I have not contacted Sonos directly yet.  Any other suggestions?  Thanks in advance.  Bruce.

What TV audio source(s) are you playing when this occurs and what audio format/codec are you passing through the TV? Do you have an audio splitter/extractor you could try to see if this still occurs when you by-pass the TV.. (see the example links below). Are you using the updated TV firmware v 04.70.05?

https://www.amazon.com/AV-Access-Extractor-Splitter-Amplifier/dp/B07D9BNVM1/ref=sr_1_21_sspa 

or...

https://www.amazon.com/NewBEP-Switcher-Selector-Extractor-Splitter/dp/B07438WJ8G/ref=sr_1_7

I’m on v04.70.12, which is the latest in the US. I have HDMI Ultra HD Deep Color enabled since the TV connects directly to the Apple TV 4K. The TV connect via the HDMI ARC port to the Sonos Beam using the bundled HDMI cable (though I tried a Belkin Ultra High Speed HDMI cable as well). Do you have your TV outputting Bitstream or PCM? What are you AV sync settings in the Sound menu? Is the Apple TV outputting Dolby Atmos to the TV? 

My TV is outputting Bitstream. DTV Audio setting is set to 'Auto', AV sync Adjustment is ‘off’.

Sonos does not support Dolby Atmos (either the DD+ or the TrueHD version) .. you need to output Dolby Digital 5.1 audio for your Apple TV.

Right, but Dolby Atmos still gets to the TV. Then the TV downsamples (or fallbacks) to 5.1 which is sent to the Sonos. 

Is content from the built-in apps showing as DD 5.1 on your Sonos? 

Er.. Afraid not, not whilst you have the TV set to pass-through, it won’t down-mix anything at all.

Well I’m getting 5.1 sound out of the Sonos. Since Atmos is delivered not as a codec but as an extension to DD or TrueHD, I assume it gets folded into the bitstream to maintain backwards compatibility. 

Prodan,

Sorry I missed the second part of your post...

With my HDMI set to 'Bitstream' & ‘Pass-Through’ (eARC is switched off) and all my HDMI connected devices set to Dolby Digital 5.1, the 'About my System’ audio in the Sonos App for the connected Beam says Dolby Digital 5.1, that’s whether I play the DD 5.1 movie source (eg. Netflix Movie) from my V6 box, my Apple TV or from the TV’s built-in Apps.

That’s really very strange?? ....I don’t see how the LG TV can do anything with the audio stream from your Apple TV when the ports  have been set to ‘pass-through’. The setting should be doing 'what it says on the tin’ ..letting the audio pass through, as if the Apple TV was connected direct to your Beam? ...Maybe that’s where your lip-sync problem lies??

Bought a beam/sub and LG C9, now starting to regret it. TV hasn’t arrived but hooked up to older plasma last night along with 2 play 1 rears  bring repurposed. Even going optical to hdmi I was getting some out of sync audio. Played with Sonos adjuster which helped as well as processing on older tv, but couldn’t get it perfect. 
 

Seriously tempted to send the Sonos back despite how convenient it is. I saw a nice slim marantz receiver and high end 5.1 speaker combo online for a great price about what I paid for the beam and sub. 
 

Seems other tv’s have this issue, but if this is isolated to LG then I’ll add it to the list of complaints. Spent month trying to deal with LG resolution issues with MacBook (but this could also be an Apple issue and not LG). 

If you played with the Sonos ‘Adjuster' and that ‘helped’ to make a difference, then that really does sound like you had your speakers ‘grouped’ rather than them set them up within a bonded setup, as the TV dialog adjuster would not have helped at all with lip-sync, in fact it would have made it far worse???

Hi: As far as I know I have updated the most recent TV Firmware.  This is in Ontario, Canada.  I am just viewing cable TV channels with Rogers Cable.  I am not certain of other settings.  I am not too keen on adding other GIZMOS.  It was a simple setting to fix that would be great, but not that huge of an issue.  May just have to live with it.  It sadly seems that as technology gets more and more sophisticated (read complex) it becomes more and more problematic.  How did we get a man on the moon?  I tried my TV on just internal speakers and I believe there is still a lip sync issue.  Even have access to several LG TVs in this building and all seem similar.  I can’t even rule out that it is also not affecting an old Panasonic LCD.  Maybe it is an Internet Cable Provider.  I would like to see a digital meter that would align the audio and video?  Perhaps for Christmas? lol. 

The Sonos devices are just speakers and so they can only play the audio when it is actually delivered to them in the correct format they support (PCM or Dolby Digital upto and including DD5.1 surround sound), so the fact you are using a Cable TV box, then it makes sense to set the audio output on that device to Dolby Digital 5.1 and then set the TV HDMI-ARC (or the TV’s optical port depending on the connection being used) to pass-through that audio stream without processing/interrupting it. The C9 certainly allows that ...and it definitely works for me with my cable box and Apple TV etc. attached to its HDMI ports.

So I just spoke to the UK support. I was told that because sounds comes out then there is no issue. As I had checked the settings there was nothing else to do and everything was working as expected. 
 

On that note does anyone know if any other OLED TVs exist that don’t have this issue. Are Sony TVs still having it or are they fixed now? I’m going to sell mine when I can find a working replacement and I’ll not be touching LG again. 

I’ve never had an issue with Vizio TVs. 
 

Audio Lag successfully conquered:

I now have the Cablebox to TV as HDMI for video. And discovered there is a Optical Output from the Cablebox which I used with Optical/HDMI adapter to run directly into the Beam. I'm going to get a 3-1 Optical adapter to ultimately connect all audio components including TV apps, BlueRay, and Cablebox.

https://jtechdigital.com/product/spdif-toslink-3x1/

This seems to be the solution for me as well. I have the J-Tech 4K 60hz HDMI audio extractor (HDMI from cable box to J-Tech, HDMI out to Samsung q60 HDMI input 1, optical from J-Tech to Playbar). Solved the problem with audio sync but I can’t get Apple TV audio without switching the hdmi inputs to the j-tech. 
Thanks

At first thought I thought the 3x1 toslink from J-Tech that MSterling linked was the solution for me but this will only work if the source of the audio/video has an optical output, which my Apple TV 4K does not. The J-Tech 4K@60HZ HDMI Audio Extractor Converter SPDIF + 3.5MM Output solved my audio sync problem but with that installed between my cable box and the Samsung the only way to get audio from Apple TV to my Playbar is to switch out the HDMI in/outputs on the extractor. I’ve searched for an extractor with multi HDMI in/out ports and toslink but can’t find such a thing. Is there a solution for this I’m overlooking?

Booner,   Is this what you’re looking for?  It would allow the HDMI from the Cable box and HDMI from AppleTV as inputs.  HDMI out to video for TV.  TOSlink output to Playbar.  If Playbar needs HDMI, then you would use the Optical to HDMI adapter on the TOSlink.

https://jtechdigital.com/product/3x1-audio-extractor-4k/

This also may be a choice.

https://www.amazon.com/dp/B07P9P9NBN/ref=cm_sw_em_r_mt_dp_U_BvZ-DbGWGATAX

Happy to report the J-Tech 3x1 audio switch solved all my audio sync problems. I have my PlayBar and 4K ATV connected as shown below. Hope it’s helpful to anyone still having lingering issues.

Cable box → J-Tech audio switch via optical
Cable box → Samsung Q60 via HDMI
4K ATV → Samsung Q60 via HDMI
Samsung Q60 → J-Tech audio switch via optical
J-Tech audio switch → PlayBar via optical
 

2019 Panasonic OLED owner here, same issues.

ARC was the main reason I chose the Beam, so pretty disappointed that the only way around this issue is using an optical splitter. 
 

Using an amp with ARC or another brand of soundbar proves to have no issues, and yet with any source or input I’ve also got this audio delay behind the video. 

the J-Tech audio switch has resolved my issues with the audio lag.