LPCM ETA for Arc?

Hey there,

I have not read every reply in this thread but I have an LG BX 65” OLED (2020), Apple TV 4K and the Sonos Arc. Apple TV Atmos content is silent for me, dead silent. All other audio types worked perfectly. I thought it was an Arc+Apple TV issue because because Atmos worked perfectly from other sources, the built in TV apps, a Sony 4K Blu-ray player, Xbox. 

But then, I unplugged the Arc from the TV and switched the audio to the TV’s own built in “atmos” speakers. Apple TV 4K Atmos tracks also did not work here, once again it was silence and all other audio types from all sources worked perfectly.

The Television is the problem here, right?

 

 

 

 

Don’t forget, these expanded Apple menus only appear IF you are plugged into the ARC (eARC) port on your TV.

These are my exact settings, and it works perfectly with everything but the Apple TV 4K...

Supposedly its that the Sonos Arc does not support Dolby LPCM yet and they are working on it according to a community manager.  This will allow the Apple TV 4K Hardware to passthrough the signal to Sonos Arc.  Internal Apps work on TV.

To answer your question is it the TV...yes, but it is also a little bit the fault of Apple and Sonos as well.

LG changed the FW in how they process LPCM and so I guess on many 2020 LG TV like you and I have, we then get no sound from the external Apple TV 4K Hardware if Atmos is enabled. Apple takes the position apparently to deliver Atmos differently and Sonos didn’t implement the Dolby LPCM at launch.

I have resolved myself to just using the internal apps on my 2020 LG i.e, Apple TV+, Netflix and Disney for now and therefore I do get Atmos on the Sonos Arc.    I am not super happy about the situation but I can not return the TV or Sonos Arc now.

Funny enough, Apple TV 4K does passthrough Atmos on my 2017 Oled to the internal TV speakers as well as the Sonos Arc.   I am not a techie and am just pointing out the items I read in other posts while I was trying to figure out just like you if my TV is a problem.  I contacted LG and Sonos and they were no help so I turned to the forums and there are a ton of people experiencing the same thing with 2020 LG models and the Apple TV 4K.  It also applies to the Xbox One X if you enable Atmos as they also send it as LPCM.

Here is the thread where they confirm they will add it.

I have a 65NANO91ANA. Just updated to:

1. Apple tvOS 13.4.8
2. Sonos 12.0.3
3. LG 03.10.25

It appears that the LPCM support is still lacking and no change on the aforementioned Atmos comments.  I have preordered and HDfury Arcana in hopes it arrives before the software updates happen or my TV return policy expires. 

Note that Arcana won’t help you here. Apple TV 4k pushes out multi channel LPCM. So, until Arc supports that format, you will have to toggle the Apple TV sound output between Dolby conversion and “auto” for Atmos.

The ARC supports MAT2.0, which is what the AppleTV 4K puts out. Just chatted with HDfury and they verified it will work. Here’s the video where they proved it: https://streamable.com/xj2fbf

You will get Atmos, but with regular surround, you will revert to PCM 2.0. It’s an annoyance with Apple TV4k and current Arc LPCM support. Eventually, this will be fixed. 

Has the LPCM support issue been fixed yet?  I’m on the fence about getting the ARC for my C9 77” with heavy a ATV 4K use. It seems there is such a crossover between Apple and Sonos that this would be a non-issue out of the gate. Trueplay is iOS only, so there is obviously an open line of communication between Sonos and Apple.  Either way, at this point, I think I’m going to compare the Klipsch 54A which is supposed to release any day and offers front and rear Atmos drivers. Then get a Sonos Amp to handle stereo music tasks in that room.  How does the Arc fair when playing music? I think I may be better served with this setup anyway.

I think the Arc sounds great with music-I have it in a 5.1 setup with the sub and two rears connected to an Amp.  I also have another Arc in a 5.1 config with the Sonos Ones.  Both sound great to me, but it’s obviously a personal preference. 
 

LPCM is not yet fixed, but you can use the built in LG apps or manually change the LG’s audio settings based on what you listen to on the Apple TV.  Takes 5-10 seconds.  Sonos will release LPCM support eventually (they announced that)-it’s not really an Apple issue but a standard they don’t yet support (they support PCM but not LPCM).  LG’s firmware used to correct for this because LG didn’t support LPCM so it would convert everything automatically, but no more.  So, LG may also release a fix to automatically convert it again. In fact, what is really broken is the “automatic” setting in the LG audio settings. But either LG fixing it or Sonos releasing LPCM support would eliminate the issue.  

Just wanted to chime in here and say I have the same problem - no sound from ARC via 2020 LG 65 NANO86TNA from Apple TV 4K when viewing Atmos movies.

To describe it as a disappointing is an understatement.