LG 43UJ630V - Audio output delay gets worse the longer TV is on (ARC/Digital-Optical)

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I have an LG 43UJ630V connected to a Samsung HW-K450. The firmware is up to date.

At first glance, the issue would appear to originate from the soundbar, but I'm almost certain the fault is with the TV and the way it processes & delivers the output signal to the HDMI ARC and digital optical outlets.

Here are my symptoms:

When the TV is turned on, the audio sync is excellent. No AV settings needed, no delay on the soundbar. Perfect.
However, over the course of a few hours the audio slowly begins to go out of sync. It gets worse and worse, until I'm forced to take action because it's so intolerably bad.
When it gets this way, AV sync settings for some reason cannot fix it. If I set the delay on the soundbar, it may temporarily correct it, but because the audio latency goes up and down over time, it's not a permanent fix by any measure.

When the soundbar is turned off and it defaults to the internal speakers, the delay seems to disappear.
I could leave the soundbar disconnected for 10 minutes, but as soon as I reconnect it, the issue returns.

However!!! - If I leave the soundbar connected and simply turn off the TV and back on again, the issue is resolved... until it slowly returns an hour or so later.
This would suggest the soundbar is not at fault here - the LG TV is.

Watching TV the last few days has not been a relaxing way to unwind at the end of the day. It's a chore, headache-inducing and incredibly frustrating.
I'm 99% sure the issue is with LG's product, and am encouraged by seeing so many others post about similar issues regarding the audio sync.
I haven't come across a single case though like mine, whereby the audio drifts slowly out of sync over the course of hours.

I've tried turning off all the potentially intensive/processor-hungry picture settings, forcing PCM output and everything else practically.
My guess is it might be resolvable with a firmware update, considering the success of a recent firmware update which resolved a similar issue for a different range of LG models, but how long should I wait until I give up and send it back?

Any advice or ideas are welcome.
 
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It went very badly out of sync again last night - and although I've tried it multiple times before with no improvement - switching from ARC to optical appeared to fix it this time.
I'll keep it connected via optical cable and wait to see if it goes out of sync again tonight.
 
Hi there. I'm afraid I don't have any advice but just wanted to say that I also have this very same issue. I have a 55UJ630v and have the ARC channel connected up to my Onkyo receiver.

I have found that when using the various smart app’s on the LG set (Netflix, iPlayer, YouTube, etc) that there is no way of removing significant audio delay.

I have tried all the audio delay options on both the TV or the receiver (or combining the two). I have also found that this problem occurs when connected via optical cable.

I do not have any issue with these apps if I use the internal speaker on the LG nor if I connect Bluetooth headphones. I also have no issues with the various sources I have connected to the receiver and then sent to the TV.
 
Just wanted to confirm that the digital optical output also goes out of sync.
It's useless.
It's probably a firmware related issue but there's no fix coming it seems. LG haven't replied to my emails explaining the problem either.
Pathetic.
It's staggering that this issue exists in the first place with so many products, how could they not have realised?
I guess I'll be sending this back for a full refund.
 
Hi there. I'm afraid I don't have any advice but just wanted to say that I also have this very same issue. I have a 55UJ630v and have the ARC channel connected up to my Onkyo receiver.

I have found that when using the various smart app’s on the LG set (Netflix, iPlayer, YouTube, etc) that there is no way of removing significant audio delay.

I have tried all the audio delay options on both the TV or the receiver (or combining the two). I have also found that this problem occurs when connected via optical cable.

I do not have any issue with these apps if I use the internal speaker on the LG nor if I connect Bluetooth headphones. I also have no issues with the various sources I have connected to the receiver and then sent to the TV.

So do you experience drifting audio delay when watching TV? With me, it appears to get progressively worse over the course of a few hours.

I've just been chatting to someone at LG. They've just filed a report for the technicians to look at, but I was told no one else has reported a similar issue, so he was doubtful it was a firmware issue.

If you do the same, Rowdenaro, we might have a better chance of resolving this.

Go to LG Chat & Email | LG U.K.

Click chat, given them a detailed description of the problem and report back.
I insisted that I wanted a continued correspondence, so if any issue is found by the technicians or they have further questions, they've got my email & phone number.
 
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I have tried all the audio delay options on both the TV or the receiver (or combining the two). I have also found that this problem occurs when connected via optical cable...
Just-so-you-know...

If people are running ARC to a receiver, the 'A/V sync' should be set/adjusted at the receiver only. And people should never, ever be tempted to activate A/V sync on the both the TV and receiver at the same time...
 
My issue is slightly different in that it occurs whilst watching Netflix and iPlayer via the LG's webos system. I have the TV connected to my Onkyo receiver via the HDMI ARC channel (HDMI input 2. All of my other devices (Freesat box,PS3) are connected directly to the receiver and then back to to the LG via that same HDMi input 2. These all work perfectly fine. I also have a UHD Blu Ray player which is set up on HDMI Input 1, The player has a separate audio only HDMI out which I have again connected directly to the receiver.

Netflix is the major thing for me. I have tried all of the suggestions found other forums in terms of switching off all of the LG's various picture processing but still can't get it to perform adequately. It seems that I can get the lip sync pretty close on some shows if I set it to -5. It feels like a couple more steps would be spot on but that's as far as it will go. But then I will play something else and it will be completely out again. Very frustrating

I have contacted LG support about and they did get back to me. They reckoned it was a fault with the TV and I should contact Very.co.uk (where I purchased it from) as it is still still under warranty and that they would organize a repair/replacement. I might go down this route but it seems to me that they are just passing the buck here and that the problem is with LG equipment. This certainly seems to be the impression I'm getting from other forums regarding various LG models
 
Just-so-you-know...

If people are running ARC to a receiver, the 'A/V sync' should be set/adjusted at the receiver only. And people should never, ever be tempted to activate A/V sync on the both the TV and receiver at the same time...

Thanks for the reply. I have tried that but my receiver will only delay the audio (which is the norm I believe). This just makes things worse unfortunately. It seems with my LG set is that the audio is arriving too late to begin with.

The LG sound menu does give you an AV adjustment option which will let you delay the audio by 15 steps but also speed it up by 5 steps.

As I said above - I feel that if I could just speed it up by two or three more steps, the audio would be perfectly in sync (for some shows anyway).

I've never seen the option to speed up the audio on any other device so it would seem that LG are aware of this potential problem. Has anyone else seen this before?
 
AO.com are offering me a free replacement.
Is there much hope in doing this?
I suspect the fault probably won't occur again with a replacement (as it's so unique), but the impression I've got from reading about AV sync issues is that LG is a particularly bad offender in this area. If the issue doesn't reoccur when I plug it in, who's to say it won't reoccur in a month or 2 when a refund/return is no longer possible?
 
Had a bit of breakthrough last night. The reply from SeeMoreDigital regarding letting the receiver control the AV sync was niggling at me so I decided to give it another go. I also remembered something else that I read on another forum about turning the TruMotion option on but setting it to 0 (do this by selecting User). I did this then I went back to the LG's A/V sync adjustment which I left on but set it to zero and then crucially switched on the bypass option. I then went to my receiver and adjusted the A/V sync there as SeeMoreDigital suggested (many thanks for that). It's not perfect but I found with the receiver set it to 20ms delay it was much improved and most importantly I could watch it without getting distracted by the lip sync delay. Word of warning I found if you are watching Netflix that if you are watching a HDR broadcast that this has a separate profile which needs to be suggested. This will also be the case for all the inputs and I'm guessing if you have Freeview coming through that it will also have a profile that will need tweaking.
 
Glad to hear it, Rowdenaro, but unfortunately my problem has only become more confusing since last posting...

Last night I plugged my Sky Box into the soundbar via digital optical, while I watched the picture signal via the Sky's RF Out as an analogue channel, thereby reducing the TV's functionality to a glorified monitor.
There's no other way to connect the sky box to the TV unfortunately, as it's an old model with only scart and composite output, so I have to use this very unusual method of programming it as an analogue channel (C68), and herein may lie the problem, more on this later...

The sound was a little bit out, about -75ms, but you would expect the visual data to take a little longer to get to the screen with this unusual setup.
It appeared not to drift out of sync for a good 4 to 5 hours.
Great. This confirmed that the problem does indeed lie with the TV, or so I thought...

I drifted off at about 10/11 and woke up at midnight. The TV was off, it must have an inbuilt sleep timer if there's no interaction for a long period of time.
While the TV was in standby, the sound was still coming out the soundbar because it was connected to the Sky Box.
Remember, the TV at this point is functioning much like a glorified PC monitor.
When I switched the TV back on, the sound and picture were out of sync by about 500ms.
I was completely flummoxed, and am still.
I thought I had deduced the problem lay at the TV's external output, but I wasn't even using the TV's HDMI ARC or digital optical outputs, so maybe this isn't the case... unless this new symptom I've described is something different, which I can't dismiss either.

Now I have no idea where the blame lies.

Is the soundbar going out of sync?
Is the TV's external audio output going out of sync?
Is the TV's picture (visuals) going out of sync?
Or maybe there's something up with the way that the TV processes analogue signals (Sky RF Out) that causes this problem. That said, when I switch over to one of the inbuilt Freeview channels ( we have an aerial input as well going through the Sky box), the problem persists. Considering my unusual setup, maybe this is why nobody else has experienced the problem. It may indeed be a firmware related issue with the TV, and I may be the only person to have reported it because who uses analogue nowadays?
I need to conduct more tests with the inbuilt Freeview. Maybe watching the Sky signal too long causes it to go out of sync, and the Freeview channels don't restore sync, but don't make it any worse. I mainly watch recorded shows on Sky+ so I can't test this easily unfortunately.

It is very notable and not to be ignored, that the av sync when plugged into the Sky box didn't drift over the course of about 6 hours (not to my eyes anyway). Usually by then I would've had to have turned off and on the TV on 2 occasions to restore sync.
So the issue I experienced last night may be a separate thing.
Still, I can't quite get my head around why that happened last night.

EDIT:
I have a really shitty scart converter (terrible quality picture and sound), so I can hook up the old sky box via HDMI temporarily.
I'm currently conducting a test whereby I have the soundbar connected to the sky box (digital optical) and the picture via the converter as an HDMI input, but I've set the sound settings on the TV to output through the soundbar AND the builtin speakers.
Initially, I've set the soundbar's audio sync settings so that it's perfectly in sync with the builtin speakers.
By my theory - if the audio from the soundbar starts to go out of sync (which will be easily detectable as it'll sound like echo), then the soundbar/internal audio is at fault (find out which by singly muting each output and identifying the closest in sync with the picture). Otherwise, it's the visual sync/unusual sky signal at fault (then I can conduct with the Sky's RF Out as the picture/builtin speaker source and see if there's any difference).
I will report back with the results.
 
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The internal speakers and soundbar have been perfectly in sync with each other all day, the picture on the TV however appears to have drifted out of sync a little bit. Only subtly, but still quite noticeable.

As strange as it sounds, I think all of this may be down to my unusual method of audio+visual delivery - via the Sky's RF Out as an analogue TV channel - and a problem in the way it's processed by the TV.
I believe I've chanced across a very rare & undetected bug in the hardware/firmware.
The TV must be calculating the visual timing incorrectly when it's given an analogue signal to process.
There's just no other way to explain all the symptoms I've experienced so far in a single theory.
Maybe a simple rounding error means the audio and visual buffers slowly go out of sync... Something like that.
I would estimate at least 99% of people don't pick up any analogue signals so have never experienced this bug.

My unusual setup is only a temporary measure until we get Sky Q, but it's still a couple weeks away so I've ordered a multi-directional Scart to AV cable. It should arrive tomorrow or the following day, then I can finally connect the sky box to the TV in a reasonably standard way. Maybe that will resolve the issue once and for all.

If only AO.com had listed it correctly as having AV input capability, it may have saved me an awful lot of bother (and £10 for an absolutely crap scart to HDMI converter)
 
I'm seriously at the end of tether.
The Scart to AV is shit. It stutters like crazy and the audio still goes out of sync eventually.

Digital Sound Out set to 'auto' as LG recommended is also crap. If I use the internal speakers + digital output sound setting, the audio delay is massive and cannot be fixed with AV sync.
Setting it to PCM resolves this for watching TV, so against LG's advice I'm doing this.

I tried leaving it on an HD freeview channel for an hour or so with internal speakers + digital output set, and sure enough - the soundbar output went out of sync, creating an echo effect.

I'm going to try getting a replacement of the same model instead of sending it back and getting a refund, this way is simpler than getting a refund and finding a new model of TV.
But I really doubt that a replacement set will resolve all of these issues.
I think it may be an issue between the sound bar and the TV, and the only way to resolve it will be by replacing one or the other.
What a NIGHTMARE!!!!
 
I've never heard of audio slowly going out of sync, it's always been either in sync from the start or out of sync.
It really sounds strange and I wish I could help but I'm not sure what could be wrong since you tried many different things.
I think getting a replacement is a good next step just to see what everything is like with the replacement.
Good luck.
 
What a headache this has all been.
I've got the TV boxed up and ready to be sent back. It's only a matter of minutes until the delivery van arrives with the replacement.
Meanwhile, I've just received an LG soundbar (SH4D 2.1), figuring I might have better luck with this.
There's a catch though - IT'S AWFUL!
I couldn't believe how bad the sound quality was compared to my Samsung KW-450.
Music sounds incredible on the Samsung, muddy and tinny on the LG.

So now I'm hoping beyond hope that my original LG TV was faulty, and this new one (arrival imminent) will not suffer the same problem of drifting audio sync with my soundbar.
But I'm >50% certain that the problem is built-in or some sort of compatibility problem. With the new soundbar I'll be able to test this.
But if I had to put money on it, I'd say the audio output from the TV is prone to going wrong like this due to a firmware issue. If this were a hardware issue, it's the weirdest one I've encountered.

Questions remain:
- Why has it not been reported by others?
- Why did the TV display go wildly out of sync one night (after a short period on standby) while the Sky box was connected directly to the soundbar?

I cannot answer these reasonably, so my theory is probably wrong, however I should note that ever since the soundbar has been connected to the Sky box, there have been no issues where the audio sync drifts over a long period of time, so despite that 1 unusual event, the Soundbar does not appear to be at fault.

The worst thing about this problem is the waiting, the difficulty with diagnosis, the lack of surety and downright confusion.
By the end of today though, even if the problem remains I should be a little bit closer to understanding it all.

Wish me luck.
 
Unbelievable.
It turns out I was correct in my diagnosis.

New LG 43UJ630V + new LG soundbar connected to TV via digital optical = the exact same problem.
When I switch the audio setting to digital output & internal speakers, you can observe just how terribly out of sync it can get:



Apologies for the crap example to demonstrate the problem, but I can assure you the internal speaker output was more or less correctly in sync with the picture, while the soundbar output is almost a whole second late.

This is with a different make and model of soundbar (LG SH4D 2.1) and a replacement TV (still LG 43UJ630V).
I plugged in the Samsung soundbar after recording the video above and the problem didn't resolve.
Also note with my replacement model I intentionally did not install the latest firmware to see if the problem may have been in the update (My previous LG 43UJ630V was up to date and had the same issue)

Assuming I've not stumbled across a rare fault twice (too unlikely to consider), the issue clearly lies with LG and this model/range of TVs, particularly the way the digital audio is processed and delivered via the outputs.

This is LG's page for the UJ630V range:
LG 43 LG ULTRA HD 4K TV | LG Electronics UK

It comes in 43", 49", 55", 60" & 65". I assume they contain very similar, if not identical internals, so I can assume the entire range is susceptible to this problem with external audio devices.

Also recall I have tried practically every audio / picture setting and it did not resolve the problem.

Considering the run-up to Christmas & the great price, I'll also assume that many people have bought this TV (or another model in the UJ630V range) with a soundbar and are experiencing the same problem right now.

What do I do now?
I'll be sure to get in contact with LG tomorrow, but this is nuts. It's almost a whole second out of sync!
How on earth was this problem not spotted earlier, and why do I appear to be the only one noticing and voicing this problem anywhere on the internet?
I've sufficiently proved that the problem is apparent across not just my TV, but countless others in theory.
I can't be the only one to have sent back a TV or soundbar due to this.

Christ, what an incompetent company.
I deserve compensation for the crap they've put me through.

Besides phoning or emailing LG, what should I do next? I'd love to hear some more suggestions.
 
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Did you get it fixed? I do not know what to do. A greeting.
 
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