LG C1 audio sync issue

Yep, I’ve got exactly the same settings, except my ATV is plugged into the Media Player HDMI port, and yes my C1’s audio is set to bypass.

This is reassuring to know. Let’s hope fingers crossed that when my replacement arrives, the updated chipset also fixes the problem, though they never stated it would. I’ll report back in a couple of weeks (assuming I can get it back that soon).

Do you have auto lip sync on the LG or Denon enabled? They’re enabled by default but do sod all in my case.
 
Yep, I’ve got exactly the same settings, except my ATV is plugged into the Media Player HDMI port, and yes my C1’s audio is set to bypass.

This is reassuring to know. Let’s hope fingers crossed that when my replacement arrives, the updated chipset also fixes the problem, though they never stated it would. I’ll report back in a couple of weeks (assuming I can get it back that soon).

Do you have auto lip sync on the LG or Denon enabled? They’re enabled by default but do sod all in my case.
I'm out at the moment but will take pictures of my settings and forward them on here. Hopefully when the revised amp arrives it should be plain sailing...... I've been waiting since July for this amp.
 
Thank you so much!
I bought mine August, but it was an old batch (pre-August 2021), which had the bug/compatibility issue. Serial number has to be over 70001 according to Denon.
 
I've been playing around with different connection methods using the C1, 3700 and ATV and for me what works the best is to connect the ATV directly to the C1 and the panasonic bluray directly to the 3700. When the ATV is connected to the 3700 it works and there no lip sync issue just that it annoys me when it take a few second for the home screen or content to appear. When the ATV is connected to the C1 the home screen and playing contect is displayed instanly without any delays. It also pass through ATMOS and is displayed on the 3700 display.

With the panasonic Bluray connected via the C1 the 3700 is unable to pick up DTS audio formats so this would need a direct connection to the 3700.

Apart from that everying works flawlessly no issues or complaints.

hope that helps
 
That’s good to know that your setup doesn’t have any lip sync issues. I still haven’t heard when my replacement AVR is arriving, but when it does I’ll make sure everything is up to date and report back on the audio sync.

If I come across a fix for the no signal image thing, I’ll let you know. I prefer to use the AVR as the HDMI switcher, so ideally I‘ll have everything going into that first and then into the C1.

Thanks for the help
 
So, i spoke to my AV dealer and he can no longer get me the X3700H until May 2022 because Sound United are prioritising all orders to Richer Sounds.

Anyway, I tried watching a few movies with the internal speakers of the TV and wired headphones to the TV, and even now I am getting lip sync issues!! There is no AVR in the chain, and it’s still happening. It happens with some movies, and not with others. For example Airplane (4K Dolby Vision) it is spot on, but The Thing (4K HDR), the audio is almost 1 second before the picture! I’m going mad.

Can you kindly share your Apple TV settings under the Video and Audio part and then your sound options on the TV and I’ll see if that eliminates the problem. Also, how are you testing the audio? Are you playing films purchased on iTunes?

Thanks
 
I was just having this issue even with bypass, AVR in direct mode, audio hdmi connected from BR player directly to AVR w/no sound going to TV and no video signal going through my AVR. I seemingly fixed it by switching HDMI Input Audio Format in TV sound settings from PCM to bitstream.

I have no idea why this setting matters when there is no audio signal even going to the TV at all but maybe that will help someone else.
 
Thanks for your reply. I have tried PCM and Bitstream and it makes no difference unfortunately for me.

So the latest is I have now tried multiple external speakers (Denon AV Receiver, Denon soundbar, and wired headphones) and all experience audio sync issues of varying amounts.

I get the audio issues whether I am using the apple TV 4K as a source, and also the internally installed apps on the TV.

The only consistent spot on method is to use the internal speakers.

I have been on the phone once again with LG technical support, and they will be sending a technician over to my house soon to inspect and run tests as they said this seems like a fault with my unit.

I will report back with their findings.
 
Thanks for your reply. I have tried PCM and Bitstream and it makes no difference unfortunately for me.

So the latest is I have now tried multiple external speakers (Denon AV Receiver, Denon soundbar, and wired headphones) and all experience audio sync issues of varying amounts.

I get the audio issues whether I am using the apple TV 4K as a source, and also the internally installed apps on the TV.

The only consistent spot on method is to use the internal speakers.

I have been on the phone once again with LG technical support, and they will be sending a technician over to my house soon to inspect and run tests as they said this seems like a fault with my unit.

I will report back with their findings.
I'm having the exact same issues, C1 65 connected to Sonos Arc and Shield Pro.. I've been having the audio before video problem for a week now I don't know what to do anymore, the issue persists with internal apps too and I think even with using the TV speakers.. let us know what the technican says please.
 
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The other day, I had a call from the TV repair technicians that LG use for my area, and they said they were to call in to take a look at the TV. So, I sat down that evening to find good examples of audio out of sync with the picture. But…somehow, it seems to be in sync!

I sat down with my wife to see if she could notice any audio sync issues, and she couldn’t. She then told me she accidentally changed the output mode on the C1 to use Internal TV Speakers + Optical Out. Then when she switched it back to just Optical Out, it seemed in sync! Could this have magically forced a sync?

Would anybody with the same issue as I have been having kindly give this a go and let me know if it helps? I do not have the AVR anymore, so can’t test this on HDMI out, but it fixed the sync with the optical out, wired headphones, and airpods connected to the apple TV.

It is not 100% in sync, it’s still about 20ms out, but it’s consistent so I can offset it, whereas before it was about 200ms and all over the place.

Also…since I last posted there have been two firmware updates, of which I cannot find the list of changes anywhere.

The engineer did arrive, but didn’t know anything about picture modes, he was just sent around to make sure I had connected the Apple TV to the ‘correct‘ HDMI port on the TV. He clearly doesn’t actually work for LG, but took notes that the game optimiser is the only spot on picture mode, as is use internal speakers, and will report it back to LG. But I found it very hard to convince him that was any audio sync issues, as it is so much better than it was before.
 
Just to add some info here

This is a common issue. I have an lg cx / denon x3700 and atv4k Gen 1

I do not know which component is at fault.

I would always plug UHD / blue ray players into the denon.

Atv to the tv - if you allow the tv to re-encode the sound to DD+ which in some cases simulates atmos, the sound is in sync across the board. You should know that all streaming services use this sound format. You are not missing out here. Nobody uses DD:HD etc

If you want to prevent weird simulations on sound and pass through the actual source, use eARC and pass through in the sound out setting. However, this does exhibit delay issues without some tweaking.

In av sync adjustment enable bypass

Now the weird thing is there seems to be an issue with LG sound settings.

Go to digital sound out
Select auto (wait for the change)
Then select PCM (wait)
Then select pass through

For some reason, switching modes forces a resync and pass through gets back in sync for all content
24hz & 50hz

Amazon seems to have an inherent issue with their app. I use 140ms delay in the audio sync settings on the denon (it’s input specific) and this seems smooth out the delay for everything.

Once you switch the audio outputs on the tv in that weird sequence shown above it sticks. But if you ever have future issues, you can redo it.

I run it this way as I prefer the AVR to run the intended sound encoding. I’m not keen on simulations. I use pure: auto sound mode on the denon too.

But just remember, you lose nothing in terms of quality by allowing the tv to convert all audio from streaming apps to DD+ This is why it syncs up as its normalised back to one standard and can sync with the video.

As I said, who knows why we have these issues. I think it’s actually that these devices struggle to process different video signals and audio tracks at high bit rates. I think it’s processing power related.

I think some manufacturers like Yamaha have computational units that do a better job.
 
@OldSkoO1 thank you! I ran your steps above where you switch to auto, then PCM and then pass through and it seems to have got the audio sync with pin sharp accuracy.
I’ve only tested a couple of Apple TV movies but so far so good.
When I receive my replacement Denon AVR I will report back if it still works, as I plan on using the Denon as the hub. Right now I tested the above with the Apple TV directly into the C1.

Thanks again
 
@OldSkoO1 thank you! I ran your steps above where you switch to auto, then PCM and then pass through and it seems to have got the audio sync with pin sharp accuracy.
I’ve only tested a couple of Apple TV movies but so far so good.
When I receive my replacement Denon AVR I will report back if it still works, as I plan on using the Denon as the hub. Right now I tested the above with the Apple TV directly into the C1.

Thanks again
No problem. It is certainly weird and I never normally believe such an illogical set of steps to solve things but it has seemed to work for me.
 
LG got back to me after the engineer visit a few weeks back, and have ordered a new motherboard for my TV to be replaced next week. Is this something I should go ahead with now that it seems I have it in sync? I do not have my Denon AVR yet (as they are all out of stock), but I would have liked to try the audio with that before I had the definitive answer, so far it works with optical out, but I do not know about HDMI yet in my situation.

I am kind of thinking that a motherboard replacement will be a waste of time, but I’d like to know what you guys think.

Thanks
 
LG got back to me after the engineer visit a few weeks back, and have ordered a new motherboard for my TV to be replaced next week. Is this something I should go ahead with now that it seems I have it in sync? I do not have my Denon AVR yet (as they are all out of stock), but I would have liked to try the audio with that before I had the definitive answer, so far it works with optical out, but I do not know about HDMI yet in my situation.

I am kind of thinking that a motherboard replacement will be a waste of time, but I’d like to know what you guys think.

Thanks
Did you get it repaired?
 
Hey @aygo1989
Yes, the engineers came and replaced the motherboard but it made no difference. They said they didn’t believe it would fix the issue, as it sounded like a software issue and hopefully LG would eventually be made aware of it and address it in a firmware update. Anyway, I technically have a new TV I suppose. I don’t know how LG aren’t aware of it, as there are countless threads stating the issue.

I also received my new Denon X3700H amp, and yep as I expected the sound is way out. What I’ve done is just set the Audio Delay on the amp to 120ms for iTunes movies, and 200ms for Amazon Prime. I can do it from the Denon iOS app discreetly so my guests don‘t realise that I’m setting it whilst the movie is playing. I can also do the PCM->Auto->Passthrough trick as we mentioned above, but it doesn’t last long before it’s all out of sync.

If anybody ever comes across a permanent fix or combination of settings that seem to work and stick then please update this thread.

Thanks all
 
I'm thinking EVERYONE must have the same problem and fewer people notice it because it appears after 2-4hoursI have the same problem with my LG CX. I use the tv as a monitor/tv so the TV is connected via ultra-high-speed HDMI cable (the best possible one), it is the only screen connected to my gaming pc (should not be a graphic card issue Nvidia GTX 1650). The problem has been there from the very beginning, 6months. At first turning on the monitor for 2-3 hours, there are absolutely no issues BUT later the sync problem appears out of nowhere. I have not yet contacted the seller or LG support because I thought it must be a software issue and they will get it fixed through updates :/. Until now I have been restarting the tv every 2-3 hours to keep the problem away.
 
I have LG C9 Yamaha RX-A2050 and a intel nuc. I had everything plugged to the receiver and everything was ok after some update maybe on the tv cause the yamaha has it's update firmware turned off I couldn't get 4:2:0 and 10bit in Windows I first though it was the new Intel graphics commander since it now has an option to choose bit depth and color space. I had the options for 8bit and 12bit 10bit wasn't showing for me. Whenever I changed from RGB to either 4:2:0 or 4:4:4 I was getting "no signal" on the tv the only way to work around it was to plug the HDMI cable from the PC to the TV then it worked, but that's when the lipsync issue came to play it's only on Dolby audio sources PCM is fine. I tried to reinstall to older Win 10 Pro from 2021 and disabled with the windows updates but still when I turned HDR on I couldn't get 4:2:0 10 bit it just said RGB and 8 bith dithering which is bad for HDR. Anyway i've tried all the stuff in here didn't help me I ended up using -100ms in LAV Audio decoder since that what I use for main movie watching. From all the topics I've read the LG is at fault here as for why my tv stopped going to 10 bit 4:2:0 when playing HDR out of nowhere I can't say.
 
I have LG C9 Yamaha RX-A2050 and a intel nuc. I had everything plugged to the receiver and everything was ok after some update maybe on the tv cause the yamaha has it's update firmware turned off I couldn't get 4:2:0 and 10bit in Windows I first though it was the new Intel graphics commander since it now has an option to choose bit depth and color space. I had the options for 8bit and 12bit 10bit wasn't showing for me. Whenever I changed from RGB to either 4:2:0 or 4:4:4 I was getting "no signal" on the tv the only way to work around it was to plug the HDMI cable from the PC to the TV then it worked, but that's when the lipsync issue came to play it's only on Dolby audio sources PCM is fine. I tried to reinstall to older Win 10 Pro from 2021 and disabled with the windows updates but still when I turned HDR on I couldn't get 4:2:0 10 bit it just said RGB and 8 bith dithering which is bad for HDR. Anyway i've tried all the stuff in here didn't help me I ended up using -100ms in LAV Audio decoder since that what I use for main movie watching. From all the topics I've read the LG is at fault here as for why my tv stopped going to 10 bit 4:2:0 when playing HDR out of nowhere I can't say.
Yamaha hasn't fixed the issue's with HDMI 2.1 via firmware update and likely never will.

Denon, Marantz, pioneer, Polk, Boston Acoustics & I think 1 more brand are all actually 1 company called SoundUnited.

Everything sound united sells they claim is HDMI 2.1 with a FIXED chipset but that is a lie. I kid you not when I say I bought. 9 different receivers that were "fixed" and returned them all because I game on my LG C1, also had a Cx and C6 (2016) model in the same series) and every single LG OLED had issues with audio if eArc was used.

The reason for this is they set their TV's up to use simulated Dolby Atmos not true Atmos. It's the same kind of fake spatial Atmos you get in headphones.

LG TV's also aren't compatible with Dolby HD, or any form of DTS. So they don't really support modern audio formats which didn't make sense to me until I got the C1 and a chance in the menu made is so very clear.

Their eArc audio is designed for LG soundbars and that's it. Yes they offer "support" for other AV equipment but it's half assed support.

Then you have the receiver companies still using the Panasonic chipset that was the cause of all the issues in the first place and they will likely use them until 2024 but I really hope I'm wrong there.

If you're a gamer and play above 60fps (hz) then the receiver will drop picture for like 10 seconds, or flash between the image & black randomly and rapidly. So 120hz gaming, which was the entire point of these new receivers just doesn't work.

I mean Yamaha has promised a fix via firmware "soon" for 2 years. Denon says theirs are fixed except I've tried nearly every model and had to return it. I bought them all directly through Denon and I Marantz websites. It's a big joke to them and the audio issues are a big joke to LG.

I've been a huge LG supporter (obviously) since the 2016 models and probably next year I'll buy yet another TV the year after I just got one and it will be a Samsung QOLED.

They don't have any of the audio issues using eArc that LG has nor do they only support Atmos via eArc or 5.1 via HDMI . They also have better picture quality with brighter panels, more colors, and higher color accuracy.

It's all such a shame... I've wasted so much time & money hoping issues I reported in 2016 would be fixed. I reported them again with the Cx which I bought day 1. I have also reported it about the C1 so that's it I'm done with LG. I'll sell this TV and happily move over to team Samsung.

LG could just let us pay for $20 got a DTS license but nope. They could fix the sync issues but nope. By the same token the companies making receivers could stop with the lying and just get a new HDMI 2.1 chipset made.

The problem is so bad that they changed the definition of HDMI 2.1 and started requiring certification on the box which honestly I think is to scare people away from paying $8 for a cable like we have been and now paying $30+

I am just so angry at all these companies... I don't think it's too much to ask that the equipment that's so expensive do what it's advertised to do.

I have an 11.2 surround sound setup that can't be properly used because no matter what I do, at least with LG and eArc I can't access formats I should be able to. On the flip side I can't hook things up through the receiver then to the tv because of the chipset issue. Yeah it would be fine when watching a movie or TV but I can't game with it and that defeats the whole purpose.
 
Hello. I have very similar setup

LG C1
Denon s660h
ELAC 3+1
Apple TV 4K
Certified HDMI cables

Firstly I run with ATV connected to denon into one of 8k port. Denon is connected to LG through eARC. I had massive audio sync issues.
ATV is setup with matched range and frame rate.

After browsing threads I connect ATV directly to LG. On LG digital sound output is on Pass Through. Im getting LPCM from ATV which is what I want. Denon is showing Multi In.
Audio sync issue is still present. Not that bad as it was with ATV connected to AVR, but still there.
Tried to bypass Match Screen and Sound in LG. That actually helped A LOT! But I can still feel its little bit off. If I try to run the same movie directly from tv's native platform i can see the difference. Its small ... but still irritating :D

The only time I dont have any sync issues is when I connect ATV to LG and set digital sound to Auto. No audio sync issue. But! There is big but. Now Im getting DD+.
And I have a question. Because my setup is 3+1 so no atmos for me. But I can hear difference between ATV's LPCM vs LG's DD+. DD+ sounds more ... enhanced. But I dont think in a good way.
To give you an example:

Batman on HBO max. Its 4K UHD Dolby vision and Dolby atmos.
Pass through from ATV sounds more balanced. Fighting scenes arent much more louder then regular scenes. Batman's punches are strong with fairly amount of bass. Footsteps are nicely balanced and so on.
Auto digital sund output encodes atmos to DD+. I liked it first. Everything was boomy. Fighting scenes were loud. Everything had more bass. But ... sometimes its too much. Like it shouldnt be like this. Or am I wrong? Batman's punches now sound too bassy and too present.

So what is going on here?
If I let pass through sound from ATV to denon, denon receives what? Atmos? Or something that is original and will decode and encode it into whatever and then distribute to 3+1 system.
If I choose auto in LG, will LG take original sound from ATV, decode and encode to DD+ and send it to denon and denon now only knows ahaaa this is DD+ and will do its magic?

So am I missing sound quality if I let LG do its auto magic? Because there isnt a way how to solve audio sync issues without this.
 
Hello. I have very similar setup

LG C1
Denon s660h
ELAC 3+1
Apple TV 4K
Certified HDMI cables

Firstly I run with ATV connected to denon into one of 8k port. Denon is connected to LG through eARC. I had massive audio sync issues.
ATV is setup with matched range and frame rate.

After browsing threads I connect ATV directly to LG. On LG digital sound output is on Pass Through. Im getting LPCM from ATV which is what I want. Denon is showing Multi In.
Audio sync issue is still present. Not that bad as it was with ATV connected to AVR, but still there.
Tried to bypass Match Screen and Sound in LG. That actually helped A LOT! But I can still feel its little bit off. If I try to run the same movie directly from tv's native platform i can see the difference. Its small ... but still irritating :D

The only time I dont have any sync issues is when I connect ATV to LG and set digital sound to Auto. No audio sync issue. But! There is big but. Now Im getting DD+.
And I have a question. Because my setup is 3+1 so no atmos for me. But I can hear difference between ATV's LPCM vs LG's DD+. DD+ sounds more ... enhanced. But I dont think in a good way.
To give you an example:

Batman on HBO max. Its 4K UHD Dolby vision and Dolby atmos.
Pass through from ATV sounds more balanced. Fighting scenes arent much more louder then regular scenes. Batman's punches are strong with fairly amount of bass. Footsteps are nicely balanced and so on.
Auto digital sund output encodes atmos to DD+. I liked it first. Everything was boomy. Fighting scenes were loud. Everything had more bass. But ... sometimes its too much. Like it shouldnt be like this. Or am I wrong? Batman's punches now sound too bassy and too present.

So what is going on here?
If I let pass through sound from ATV to denon, denon receives what? Atmos? Or something that is original and will decode and encode it into whatever and then distribute to 3+1 system.
If I choose auto in LG, will LG take original sound from ATV, decode and encode to DD+ and send it to denon and denon now only knows ahaaa this is DD+ and will do its magic?

So am I missing sound quality if I let LG do its auto magic? Because there isnt a way how to solve audio sync issues without this.
Ok so firstly I have it on auto in LG sound still gets lipsync only in Dolby formats I can fix it from my LAV Audio decoder -100ms fixes it .
For your setup your AVR doesn't support Atmos so its DD+, since streaming atmos is 5.1 anyway it doesn't really matter. As for the punchy base try direct sound and if it's still punchy just lower the subwoofer from the AVR or bass as whole.
 
Ok so firstly I have it on auto in LG sound still gets lipsync only in Dolby formats I can fix it from my LAV Audio decoder -100ms fixes it .
For your setup your AVR doesn't support Atmos so its DD+, since streaming atmos is 5.1 anyway it doesn't really matter. As for the punchy base try direct sound and if it's still punchy just lower the subwoofer from the AVR or bass as whole.

Even on auto? Damn ... but glad that you solved it with decoder.

Yeah atmos is out of the table. But what is interesting to me is how pass through sound is different than auto.
Because in the end it shouldnt be.

ATV is sending LPCM audio. Which is atmos? Or apples MAT whatever format? Or it detects that ok im connected to something that is not atmos doable so I will send something else but still in LPCM. Denon then gets this audio and will decode it? It has to do something to be able to distribute sound to speakers.

If I set my tv to auto, it gets LPCM audio from ATV and decode it to DD+ and send it to AVR and AVR is happy and distribute it to speakers.

So even if ATV in pass through will send highest uncompressed audio to AVR, AVR still has to lower it to something it can play ... which is DD+, right? Because that should be the best it can play.
And when sound is different on auto and passthrough it means, that somebody is doing bad job at decoding :D either my TV or denon.

And definitely denon has issues with LPCM. Not that it cant play it, but I think it doesnt really know what to do with sync and stuff. I mean dolby inside LPCM. Because LPCM is just uncompressed audio and it can be 5.1, DD+, atmos .... whatever.

And question which sound (in my case) is better ... or rather has higher quality. DD+ or LPCM whatever from ATV. Or who is doing better job at decoding. AVR with LPCM or TV with LPCM (and then sending DD+ to AVR)
Which sound I like more is subjective :) and highly influenced by forums :D I read that LPCM us uncompressed therefore better so I guess I should like this sound more then DD+ :)

EDIT:
Forgot to mention. If I set ATV to output only DD (not plus) no sync issues. Thats why I think Denon struggles with LPCM dolby audio.
 
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I tried everything in this thread and nothing worked.

What appears to have reduced the delay so as not to be noticeable to human sensory processing (used my wife as a blinded subject) - was setting video processing to bypass in the Denon receiver - even the "game mode" adds some visual inout lag which is nuts.
 
Ties in with some of the observations that the Denon chokes on high bandwidth video data - eg 4:2:2 content. This appears to have reduced the processing overhead just enough for the Denon not to be the bottleneck.
 

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