Use the Pass Through setting for Digital Sound Out rather than Auto. This should help with the lip sync issue.
When using the PCM setting on the TV, you will only get Stereo PCM audio.
When playing stereo content, the Sonos sound bar will perform an audio up-mix of the stereo signal to create a simulated surround sound. This means you’ll still hear most audio out of the front channels, but the surround speakers will play what is determined to be ambient audio.
Thank you for the explanation of why PCM is producing surround output; I thought that might be what was happening.
Regarding Pass Through with Auto/Bitstream, in the configuration with the Beam, on the TV I can turn off AV Sync Adjustment or select Bypass in the AV Sync Adjustment setting. Not sure what the difference in those options is, but both still leave the dialog out of sync. … In the configuration with the Ray I do have dialog sync off and it seems okay.
Is there not a Pass Through option under the Digital Sound Out setting on the TV?
Yes and No…. “pass through” is only an option with Optical, not HDMI ARC. I don’t seem to have a dialog sync problem with the Ray using optical, just the Beam using HDMI ARC.
The options are:
Sound > Sound Out > uTV Speaker, Optical, ***HDMI ARC***, etc] > cAuto or PCM]
Sound > Sound Out > uTV Speaker, ***Optical***, HDMI ARC, etc] > Digital Sound Out uAuto, Pass Through, PCM]
Sound > AV Sync Adjustment > n*On* or Off] > if On, HDMI ARC 1-10 *3*] or Bypass
Hi @twrva ,
Were you every able to resolve this issue with the beam using HDMI Arc? I’m having the same issue with my LG HDTV. Lip sync issues vary depending on content when using the “Auto” sound setting. PCM is the only way to fix the lip sync issue that I’ve found, however this is not ideal for a 5.1 setup.
Thanks!
Mark
After much research, the short (expensive) answer is that I think replacing the TV with a newer model that supports HDMI eARC should “automatically” solve the lipsync problem with Dolby Digital between the TV and Soundbar. I will be interested to see how well this works for different content sources. I have ordered a new TV and will follow up with the results.
After much tweaking, I have found a solution that seems to eliminate the lip sync issue for me using the Sonos Beam Gen2 + 2 Sonos Ones and an LG UJ600 series TV. The combination of settings on the TV that appears to work for me is the following:
- Sound > Sound Out > [HDMI ARC] > [Auto]
- Sound > AV Sync Adjustment > [On] > Bypass
- Video Setting: Standard Default (not too sure if this matters, but including here anyway)
In my case, I was using an Apple TV 4K to stream content. I was experiencing lip sync issues until I did the following:
- Set video output to 4K HDR with 4:2:2 chroma.
- Changed Audio Format to [Change Format] and selected [Dolby Digital 5.1]
- Performed [Wireless Audio Sync] calibration (not sure this is necessary either, but including just in case)
The bolded setting above was really what did the trick for me. When left on [Auto], the Apple TV 4K would output the audio in LPCM which seems to have been adding audio delay. I’m not an expert in audio encoding/decoding by any means, but even if you aren’t using an Apple TV, it may be worth checking the audio output of your streaming device (if you are using one).
All this being said, I do think upgrading to a newer TV makes sense to get the most out of a Sonos setup - even for myself. I imagine eARC eliminates this sort of delay due to the increase in bandwidth. I look forward to hearing your success story!
I have upgraded to a 2022 model LG TV. In addition to eARC support, this TV has a faster processor, and newer version of LG’s WebOS. Unlike the 2019 model TV, connected to the Beam (Gen 2) it seems to (so far) have no lip-sync issue with Bitstream/Dolby, with or without eARC enabled. … I say “so far” because in the past the lip-sync issue with ARC (using any setting other than PCM) varied with video content sources and time (i.e. how long the devices went without a restart between the use of different content sources), so I will follow-up if my experience changes.
The newer TV, in addition to working “automatically” better, offers more advanced audio settings. I have not yet experimented with every option, but here is what I am using that works:
- Sound > Sound Out = HDMI(ARC)
- Sound > Advanced > Digital Sound Out = Auto
- Sound > Advanced > HDMI Input (for the video source) = Bitstream
- Sounds > Advanced > eARC = Enabled
With my primary HDMI video source as a Direct TV stream box, and the Beam connected to the TV’s HDMI eARC port, the Sonos App reports the Beam is receiving Dolby Multichannel PCM (either 5.1,5.0 or 2.0 depending on the content). If eARC is Disabled the Beam reports Dolby Digital Plus. Both of those sound great, better than the Stereo PCM reported if Digital Sound Out is set to PCM.
The goal to resolve the lip-sync issue seems to be reached, but I am not certain that eARC solved it, the newer TV, or both. … In Sonos’ FAQs for Beam (Gen 2) it does say “For greatest compatibility, eARC is recommended.”
@twrva If possible, set the Digital Sound Out setting to Pass Through instead of Auto.
@GuitarSuperstar Thank you for remining me to try Pass Through. The older (2019) LG TV did not have Pass Through as an option with HDMI ARC (only optical), The newer LG TV does.
So with Sound > Advanced > Digital Sound Out = Pass Through the Beam says it is receiving Dolby Digital Plus instead of Dolby Multichannel PCM. This is the same with eARC selected or not. At least with eARC enabled (I didn’t observe it long enough with eARC disabled) it looks like there is no lip-sync issue. If I observe otherwise later, I will follow-up.
The sound quality from the Beam seems just as good with either Dolby Digital Plus or Dolby Multichannel PCM, both better than Stereo PCM. If everything else is equal, it seems to make sense to use Pass Through since that’s reporting what the Direct TV Stream box is set to output.
