Beam and LG OLEDs -Audio delay over Dolby DIgital still a problem?

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What’s super annoying is that this would actually be a valid solution, and resolve the issue in almost all cases, if SONOS weren’t stubbornly refusing to support 6 channel PCM.

@Ryan S Will this ever be added? I appreciate SONOS are limited in their ability to resolve the root cause of these problems, but you seem to be taking very little action with changes you are able to make to help the situation.
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I'm always happy to pass along the request for LPCM 5.1 support, though I'm not sure how many TVs are able to pass PCM with anything more than stereo audio. It's always good to ask, though I can't provide a roadmap or idea on if it'll be added one day.
Just got my beam and I am using it with a LG OLED B7. I haven't noticed any lip sync issues so far. I am playing from an Apple TV 4k (set to output only dolby digital) and passing the audio via ARC (TV passthrough set to auto, if you set to PCM you will only get 2 channels instead of 3 on the beam).

@Ryan S As far as I am aware it's not possible to pass LPCM 5.1 via ARC, ARC doesn't support the bandwidth and neither does optical (new eARC supports but few TVs have it). I also can't find a way to have the Sonos Beam take an HDMI directly (not via ARC) even if that HDMI is only carrying audio. So it seems due to the input limitations on the beam there is literally no way to get uncompressed 5.1 through to the beam 😞 The limited inputs would still support DTS 5.1 if Sonos added the codec support. Considering the many limitations this would be the least Sonos could do for it's customers.

But unfortunately these limitations still leave Nintendo switch owners and anything really that needs 5.1 PCM out in the cold. Personally I won't bother adding surrounds to my Beam because of these limitations. As far as I know this is why most decent soundbars include multiple HDMI in's and have the soundbar be the hub that passes just the video through to the TV rather than using ARC. This also helps with lip sync issues but brings in new complications like having to find a soundbar that has 4k dolby vision passthrough for instance...

TLDR: The beam is a great 2.0 soundbar but do your research in a big way if you plan on adding to it or want 5.1
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Hi Atlas, you're correct, the Beam only has an HDMI-ARC connection, and is designed to receive the audio through there, linked with the TV directly. The industry is very slowly adopting eARC, as you said. It's only currently being used for future-proofing, where it's used, since not much out there makes use of it.

isn't the Switch outputting LPCM 5.1 via HDMI in already? I was under the impression HDMI could take the bandwidth for that, but I could be wrong.

As to using the Beam with surrounds, they add a lot to the audio, especially when you can get Dolby Digital to the Beam. Most streaming services these days use Dolby Digital, and most TVs that I've worked with from the last 3-4 years have all been able to pass it over HDMI, including the LG OLEDs.
You are correct HDMI can carry 5.1 LPCM but apparently the arc hdmi port on the beam won’t accept a std full hdmi audio (not arc) so that’s where the hope lies if they can firmware update the beam to support a std hdmi input and accept 5.1 LPCM, then I think we could split off the HDMI with an extra piece of hardware not ideal but a potential workaround.