Audio Delay for HDMI Connected Dolby Sources
I recently purchased a C9 OLED (firmware 03.60.04) and SL8YG soundbar (firmware main 5484640-157053), and have been experiencing large audio delays of up to two seconds when playing Dolby content from an external HDMI device through the HDMI ARC port between the TV and soundbar.
As the C9 supports HDMI 2.1, I have all of my HDMI sources connected directly to the TV. This allows me to take advantage of VRR, ALLM, etc. Whilst I understand that the SL8YG does not currently support eARC (I am hoping this will be released in a future firmware update), it does support DD+ over ARC. This allows the TV to passthrough Dolby Atmos content using DD+ rather than Dolby TrueHD over ARC to the soundbar.
The problem, however, is that only PCM and DTS are passed through the TV without introducing any audio delay. As soon as the source switches to Dolby related content (Dolby Atmos, Dolby Digital, etc.) there is a significant delay in the audio being transmitted to the soundbar. I have bought certified premium HDMI cables, which have made no difference. I have also tried every possible configuration in the TV setting menu (AV Sync Adjustment, Bypass, etc.), all of which have made no difference.
The reason why I know the TV is at fault is because all internal apps on the TV (e.g. Netflix) do not experience this issue with Dolby content. My 4K Bluray player (Sony UBP-X700) does not experience this issue either when it is connected to the HDMI in on my SL8YG - the audio and video are in perfect sync. It is only external devices that are connected through HDMI directly to the TV and have to pass audio over HDMI ARC that experience this issue. FYI, I have verified that Optical also experiences this problem.
A great test is to plug an Xbox One X into HDMI 1 on the C9 and an SL8YG (HDMI ARC) into HDMI 2 (ARC) on the C9. From the Xbox audio out settings, you can manually set PCM which works perfectly (no delay), DTS which works perfectly (no delay), but Dolby Digital or Dolby Atmos will experience significant audio delays. Further, if you leave the Xbox set to Dolby Atmos and then override the C9 'Sound Out' to be PCM rather than Passthrough, the delay is improved (as a rough guide, passthrough of Dolby encoded content would be around 1s whereas decoded to PCM would drop this to around 300ms). This highlights that there is a problem with the way that the C9 is processing Dolby content from external HDMI connected sources, which causes the audio to lag the video - something that cannot be manually fixed by any available adjustment, not that this would be a viable solution if you wish to use other advertised features of the TV such as ALLM.
I have reached out to LG support a number of times but have been unable to advance this discussion to the appropriate engineering team. Can you please pass this information on to the relevant engineers and advise on when we can expect this functionality to be fixed?
0:00 - 1:00 - LG C9 Audio Settings and Firmware Version
1:01 - 1:20 - Issue with LG C9 not being able to receive 5.1 or 7.1 uncompressed (this should work regardless of whether ARC is being used or not, as the TV can convert 7.1 uncompressed to bitstream output for ARC)
1:21 - 1:40 - Stereo Uncompressed (perfect, no noticeable audio lag)
1:41 - 2:08 - DTS Digital Surround (very good, no noticeable audio lag)
2:09 - 2:40 - Dolby Digital (poor, up to half a second audio lag)
2:41 - 3:15 - Dolby Atmos (very poor, up to a second or more of audio lag)
3:16 - 3:48 - Stereo Uncompressed (perfect, no noticeable audio lag)
As the C9 supports HDMI 2.1, I have all of my HDMI sources connected directly to the TV. This allows me to take advantage of VRR, ALLM, etc. Whilst I understand that the SL8YG does not currently support eARC (I am hoping this will be released in a future firmware update), it does support DD+ over ARC. This allows the TV to passthrough Dolby Atmos content using DD+ rather than Dolby TrueHD over ARC to the soundbar.
The problem, however, is that only PCM and DTS are passed through the TV without introducing any audio delay. As soon as the source switches to Dolby related content (Dolby Atmos, Dolby Digital, etc.) there is a significant delay in the audio being transmitted to the soundbar. I have bought certified premium HDMI cables, which have made no difference. I have also tried every possible configuration in the TV setting menu (AV Sync Adjustment, Bypass, etc.), all of which have made no difference.
The reason why I know the TV is at fault is because all internal apps on the TV (e.g. Netflix) do not experience this issue with Dolby content. My 4K Bluray player (Sony UBP-X700) does not experience this issue either when it is connected to the HDMI in on my SL8YG - the audio and video are in perfect sync. It is only external devices that are connected through HDMI directly to the TV and have to pass audio over HDMI ARC that experience this issue. FYI, I have verified that Optical also experiences this problem.
A great test is to plug an Xbox One X into HDMI 1 on the C9 and an SL8YG (HDMI ARC) into HDMI 2 (ARC) on the C9. From the Xbox audio out settings, you can manually set PCM which works perfectly (no delay), DTS which works perfectly (no delay), but Dolby Digital or Dolby Atmos will experience significant audio delays. Further, if you leave the Xbox set to Dolby Atmos and then override the C9 'Sound Out' to be PCM rather than Passthrough, the delay is improved (as a rough guide, passthrough of Dolby encoded content would be around 1s whereas decoded to PCM would drop this to around 300ms). This highlights that there is a problem with the way that the C9 is processing Dolby content from external HDMI connected sources, which causes the audio to lag the video - something that cannot be manually fixed by any available adjustment, not that this would be a viable solution if you wish to use other advertised features of the TV such as ALLM.
I have reached out to LG support a number of times but have been unable to advance this discussion to the appropriate engineering team. Can you please pass this information on to the relevant engineers and advise on when we can expect this functionality to be fixed?
0:00 - 1:00 - LG C9 Audio Settings and Firmware Version
1:01 - 1:20 - Issue with LG C9 not being able to receive 5.1 or 7.1 uncompressed (this should work regardless of whether ARC is being used or not, as the TV can convert 7.1 uncompressed to bitstream output for ARC)
1:21 - 1:40 - Stereo Uncompressed (perfect, no noticeable audio lag)
1:41 - 2:08 - DTS Digital Surround (very good, no noticeable audio lag)
2:09 - 2:40 - Dolby Digital (poor, up to half a second audio lag)
2:41 - 3:15 - Dolby Atmos (very poor, up to a second or more of audio lag)
3:16 - 3:48 - Stereo Uncompressed (perfect, no noticeable audio lag)
Answers
I followed the process suggested by DeluxeMonk and it worked. What I noticed - just to add some information - was that under the AV Sync Adjustment, the slider for HDMI ARC (that ranges from 0 to 15) *had been* at 0 (only allowing it to be moved to the right which further delayed the audio), but after implementing the described process, the slider was at the high end (to the right, at setting 15) and allowed for moving the slider to the left (which delayed the video). This allowed adjustment of AV synching in the needed direction.. However, I turned Bypass to "on" and the synching was fine. Just an FYI with some info.
Hello, I can recommend if you check on Panasonic Forum's home page for some recommendations too since the connecting device is a Panasonic device.
Time ti fix this shitt.... never got dome worse support
did it work for you?
I powered off all devices to make sure it wasn't a fluke that reset after start-up, and the sync is still in check!
I powered off all devices to make sure it wasn't a fluke that reset after start-up, and the sync is still in check!
I have a little more data to share on this delay issue. I have the LG C8 65" and the LG SL9YG connected over HDMI (ARC - Port 2) w/SPK8-S surrounds and I've experienced the following:
Nvidia Shield (2016 version) No delay with HDR Atmos, TrueHD 7.1, or DD+ (TV HDMI Port 3) Plex runs on this box and this is the machine I watch my 4k connect on (file sizes range from 20GB to 110GB). Output set to 59,940Hz, YUV 420 10bits, Rec.2020
ATV4 some delay with HDR/Dolby Vision Atmos, TrueHD 7.1, or DD+ (TV HDMI Port 1) - Not as Bad as reported but still an issue with Netflix. Infuse is intermittent based on the movie. Plex converts all content to PCM (Set the audio output to 5.1 for family use because they are not as finicky as I am about sound quality). Output for video is Dolby Vision 60Hz. When I reduce this to Dolby Vision 50Hz or 30Hz the lip sync issue goes away completely (however this is unwatchable from a video processing standpoint)
All of my cables are 4K HDMI Cable 5 ft High Speed (4K@60Hz, 18Gbps).
I ran a bunch of tests connecting my AV receiver (Sony STR-DN1080) over ARC instead of the soundbar and didn't have any delay issues on any of my devices connected to my TV. This makes me think that this issue is with the soundbar, not the LG OLED. It could be higher refresh rates with the XBOX systems being described here.
...Now before you start asking my am I using a soundbar system when I have that receiver? It's because I had it set to 2.1 with a pair of B&W CDM-7SE w/earthquake sub and I wanted to whole Atmos experience (don't have the room for a full sized 7.1 system in my room).
The sound quality of this LG system is awesome with the Nvidia Shield. I wish the ATV didn't have the issue.
My understanding of it is that eArc's lip sync correction works by every device in the chain reporting its processing delay. The AVR or soundbar then takes those values and calculates how much to delay the audio for it to be in sync. This happens regardless of audio format you send it.
You have a point though that the process above seems to assume that the image is delayed, not the sound. That would indeed suggest that it might be something else that ends up reducing the delay and that the lip sync correction might simply add the finishing touches (if anything). Implementing eARC could simply have forced LG to address the audio delay to properly implement the mandatory parts of the eARC spec.
I should also probably read the eARC specification. I've already been meaning to look into how the audio format handshake between the TV and sound device works. :)
I’m not sure it’s the lip sync correction that is fixing the issue. I think LG is just passing it through unaltered on eARC when set to passthough but doing something with it that adds delay on ARC, even when set to passthrough. Baffling that they can't just send it through and do nothing.
My reasoning here is that when connecting the Sharc, Atmos on the Xbox Series X (I had already swapped from the One X so can’t comment there) also works with no lag. Unless “lip sync” is just a feature that adds time-codes to the audio and video, which I thought had always been there otherwise how was anything ever in sync when you skip around, and the Xbox also sends them? Correct me if I am wrong here.
I should probably look into how it works.
Annoying that I have to.
You're welcome! I only wish I had an answer that didn't require replacing hardware. I guess pestering LG about it is the only other option. :(
Are you able to confirm if the Sharc is able to passthrough Dolby Digital 5.1ch Bitstream without any delay via its Optical Out?
I have yet to find someone who can confirm this for me, as the majority either uses the HDMI connection and/or Dolby Atmos, uncompressed or other HD audio formats.
Best I got was someone try Dolby Digital 5.1ch on an Xbox Series X via the Sharc's HDMI out (and confirmed it removed the +100m delay noticed with the sound outputting to C9's Internal Speakers), but they couldn't get sound from the Sharc's optical, apparently due to a misconfiguration on their AVR, which they did not troubleshoot further...
If I was an USA resident I would've already ordered and tested it myself, but I'm in Europe, so shipping and import costs are no joke. Even if I were to return it for not working with my situation I would be taking quite a loss...
Hoping someone with a console with some time to spare and SPDIF cable lying around + AVR with Optical Input will appear someday.
Many thanks, mate!
That's great to hear, and it makes sense. I probably got thrown off by initially not noticing that this forum shows newer replies first, not last. :D
I agree that LG should at least come out and comment on this if they really can't fix it for regular ARC.
Yes, you understand it correctly. The SHARC adds eARC which includes a mandatory "Lip Sync Correction" feature which is what apparently fixes this. This assumes your TV has eARC support though, like you said.
I found only this review https://webproductradar.com/best-av-to-hdmi-converter-for-n64
Seems interesting.
Can someone please advice if understan correctly, that for Sharc to fix the issue, the TV at least should support eARC
so in my case - LG C8 + SK9Y soundbar, when neither LG C8, nor SK9Y support eARC, it would not do the trick?
I should at least upgrade TV to C9 or CX AND use SHARC to fix the sound.
OR upgrade bot TV and Sound to both be supporting eARC, then the issue would be fixed without SHARC?
Unfortunate though that this is somewhat unfixeble in my case without changing equimpment
No. The issue is not present when using eARC, that's why the Sharc fixes it and why it's so frustrating that LG won't.
So this is still an issue even when connected to an eARC soundbar or AVR?
Why would the Sharc fix it? From what I understand, it only acts as a go-between in this case that implements eARC (including the automatic lip-sync which is part of eARC) and then sends the audio to your AVR, where the latter happily decodes the audio since it thinks the source was connected through it.
Need advise how to convert av to hdmi?
Unfortunately, I have no way of testing optical out.
Sorry. :(
Is it possible you could test if it fixes audio lag/delay when using regular Dolby Bitstream on the source + Sharc's Optical Out?
Probably test would possibly by the XsX or PS5 outputting simple Dolby Bistream (no Uncompressed, Atmos or any type of HD audio).
Wanted to find a way to keep using Optical audio devices and the regular Dolby 5.1 with PS4 games, without the current HDMI 100ms audio delay on the C9.
Still looking for someone using that setup or willing to test...
It's hard to order it just to test myself, as I risk losing a lot with customs and return shipping fees, unless I'd try selling it.
Would really appreciate anyone to confirm this.
I can only speak for myself, but it seemed to fix it for me without having to do any adjustments. I have a Denon AVR that's plugged into an LG C9.
Hi. The Beam doesn't look to support Atmos/DD+, so I don't think it would have been having this specific issue in the first place. unless I (or the web page) is wrong?
I have all 48G cables and the issue is still present. It seems completely related to the way LG do the ARC passthrough where they obviously aren't just passing it through, they are doing something to it that adds delay, and they refuse to fix whatever that is and tell us it's "within manufacturers specifications" but won't provide those specs..
Hey all - I have a 2019 B9 and a Sonos Beam-based 5.1 setup connected via HDMI ARC and it appears I have fixed the problem by buying certified HDMI 2.1/8K-compatible cables from Amazon. In Canada, the link to product is: https://www.amazon.ca/gp/product/B081NTWGYN/
YMMV but I've tried it now on both internal Netflix and Disney+ apps and the same apps running from an external Android TV box.
Good luck!
You're probably tired of hearing "me too" comments, but I'm experiencing the same issue. I have an LG C9 OLED TV, and an LG SN7R sound bar. You'd think an LG TV would work well with an LG soundbar, but nope. Standard 2 channel sound (PCM) works fine, but Dolby (and especially Dolby Atmos) has a significant delay. It works fine if I plug the device into the soundbar directly, but that has its own issues (the soundbar only has one HDMI in port, and I lose several HDMI 2.1 features that my Xbox Series X supports).
I'm looking at buying a Thenaudio SHARC as it seems the consensus is that this fixes the issue, but it's crazy to have to buy a $150 device to work around issues on a $2000+ TV. If a third party product from a small company can fix the problem, why can't a huge company like LG fix it?
Now with firmware 1.51 the sharc works. The soundbar does not power up automatically with the C9 but if i press volume up/down the soundbar power up.
Thanks.
After giving up with LG Support at the start of the year I'd just left this issue alone and left the Xbox in none Dolby Mode and the Sky Q box directly in to the soundbar. However I started to get really annoyed with the soundbar/tv not always picking the right output when switching between internal apps/Sky so I thought I'd try everything over ARC again after the last few updates have rolled through.
Weirdly I no longer get any delay at all when watching Sky in Dolby Digital+ mode including atmos content & I'm able to run the Xbox One in Dolby format too.
However still incredible delay when switching the xbox to atmos, so will also be ordering a SHARC soon.
I’ve been following this thread for a while now, and I’m about to purchase a thenaudio sharc.
But I’m curious: is the sharc, a solution for all the lipsync issues or do I need to switch it on/off or set the delay for different types of input or different kinds of sound.
for example: the delay from my xbox is not always the same, dolby atmos is a huge delay and dolby digital less but still a delay.
the delay from lg apps in the tv is not same, and my settop box (connected to the tv also) Has no delay.
Is this the magic device that solves all these issues, without having it switching on and off, or configure it for all different sources/devices/sound settings?
Having literally ordered my Sharc yesterday, LG releases 5.00.03 today, so of course they would have fixed it....
Let me save everyone the time, it does not resolve this issue.
I did not cancel my order.
@Snake231088 Can you please confirm that you have nothing else connected to the TV when performing these tests? I performed the following steps to get everything working.
I have problems connecting my C9 with the SL8YG soundbar via the SHARC device.
@DJ_GLiTCH I hope you can help me by explaining how you connected the various devices.
I connected an HDMI cable from the HDMI 2 port (ARC) of the C9 to port 1 of the SHARC device and I connected an HDMI cable from the HDMI OUT port (TV ARC) of the SL8YG soundbar to port 2 of the SHARC device.
In this configuration I noticed that the display of the soundbar no longer shows the message ARC. The soundbar remains on OPT and you will not hear anything. When you set the soundbar to HDMI, the soundbar still does not hear anything.
I then moved the HDMI cable into the HDMI IN port of the soundbar, but the soundbar does not detect anything automatically and only by changing the source of the soundbar to HDMI for a second you hear something and then the soundbar returns to OPT and no sound comes out.
The only way I can hear audio from the soundbar is to use the optical cable from the SHARC device to the soundbar. But I did notice some audio drops out anyway.
@DJ_GLiTCH how did you manage to connect the devices? On your SL8YG what is written on the display? ARC? HDMI? OPT?
Thank you very much.
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