Hi @bignicknicknick 

I appreciate the sentiment, and I will try, but please don’t expect much - this has been requested many times, and the answer is the same each time.

Please also note that it is considered normal, which is why it gets “brushed off” as such.

Hey, I just wanted to flag this since I have the luxury of owning both a PS5 and Xbox Series X, an Apple TV 4K, and a LG CX and Sony X900H. I've hooked up all items to Arc + Sub + SL Ones, and have tested Sony’s Atmos sound bar too.

It doesn’t matter which TV, or which console, but outputting to LPCM 5.1 shows up as Mutichannel PCM 7.1 in the Sonos app… and sounds noticeably softer/muted compared to Dolby bitstream.

But flip side, moving to Dolby bitstream on either device ends up resulting in some sort of audio delay. That delay seems like it’s more on the console makers; I don’t have this issue with Apple TV or either devices. And both TVs support eArc and have passthrough enabled. But Multichannel 7.1 and LPCM sound issues are clearly a Sonos issue.

Not sure Sonos has a lot of clout with LG, to be honest. Sonos doesn’t purchase their TVs in large numbers, nor is there any revenue sharing between the two companies. As he suggested, it’s likely that individual voices such as yours carry as much, if not more weight, since you’re a paying customer, and a voice that may affect other purchasers.

That being said, I suspect Sonos does pass on some level of data to them. How much it is valued is anyone’s guess. 

Thanks, Also the other recent thread I posted similar about the LPCM 7.1 output issue on LG oleds, where all 5.1 audio is output as multichannel pcm 7.1, when the devices are connected direct to an LG oled and passthrough is set on the LG

Such as Xbox series x set to uncompressed 5.1 outputs as multichannel pcm 7.1

or

Apple 4k tv all DD 5.1 audio is output as multichannel pcm 7.1 

Clearly an issue LGs side it seems, but I have got nowhere with them to get the issue raised and fixed, many others have same problem. Perhaps Sonos could nudge LG to investigate.

Hi @ledzep1 

I understand your point, but the issue may be due to the TV not being physically able to passthrough LPCM and so it encodes it to Dolby Digital (which may include volume adjustment or dynamic compression at either the compression or decompression stages), or it could just be due to a setting on the TV. Without any details (or diagnostics) it’s impossible to determine. In most cases we recommend getting in touch with our technical support team first, so we can confirm the issue or fix it, but if an Arc works with one source correctly then it works as it should and any other issues must be induced either at the source or the TV, assuming all codecs remain the same.

However, it’s generally customer contact volumes that drive a company to implement changes. Regardless of the level of skill/knowledge of a support agent, the details of the issue are recorded for data analysis and trends are flagged, so just getting in touch and explaining the issue should be enough for this to work. If Sony (just for example) came to us and reported a compatibility issue with a combination of our and their products, but not a single customer of ours had reported any such thing, I can’t see us considering it a priority. If it was a TV model yet to be released, then I’m sure we’d work together prior to the product launch, however.

Having said that, I will see what I can do to raise this issue internally for investigation.

Hi @renexxxk 

If apps on your PS5 are a lot quieter than your TV apps, perhaps you should be asking Sony for a fix?

The Arc is not going to think “he’s playing it from a PS5, I think I’ll be quieter than usual”. It plays the feed it’s given. As it plays the feed from the TV apps without issue, it’s working correctly.

If the PS5 is not responsible for the lowered volume, then your TV is.

I truly do understand the frustration you’re probably feeling, but in this case there is nothing that we can do. I recommend you stick to the TV’s apps, if the PS5 doesn’t have a setting that will fix the issue.

Hi @bignicknicknick 

If any change is ever implemented, there’s a very good chance that you will know before I do. If I do find out before you do, there’s a very good chance I would not be free to share it the information with you anyway.

So, no, I don’t have any further information to share, I’m afraid.

Hi @Naekyr 

@bignicknicknick’s Apple TV will apparently only output Atmos or Dolby Digital, not both, or only LPCM, depending on the setting.

Anyone wants to see what I am talking about....go to Paramount+, open Arrival and watch about five minutes worth from about the 32 minute mark. This will be in Multichannel PCM. This has far more punch than anything else I have listened to in multi channel PCM. Is it just Paramount? Or is it how the studio filmed this? Or a combination of both? But this five minute test alone will show you there is far more than just Sonos going on here. I can also tell you this, the original Jurrasic Park when it was on Max, would blow the windows out on the TRex growl and that was LPCM. It now isn't on Max and can only be watched on Spectrum. Same exact scene is coming through in LPCM like Max....and the entire thing has maybe half the punch it used to have when it was presented on Max. I haven't dealt with BluRay in forever since they shoved us all to streaming, but I'd love to hear what people get when they put in old BluRay disc's of movies such as Days of Thunder. Currently that's only available on Paramount+ and you have to crank the hell out of your system to even hear it. I use to own that  movie on disc and I know om bluray it had a massive soundstage...now on streaming it is awful.

Hi @Missionsparta 

One thing I can guarantee is that your streaming services are not providing you with LPCM - something in your playback chain must be decoding to it prior to your Sonos equipment receiving it, as LPCM is completely uncompressed and it would take too much server bandwidth to supply everyone with uncompressed audio (not to mention that storing thousands of movies with LPCM would take a lot of unnecessary space).

The only place you’re ever likely to receive a movie with LPCM in the original stream is from BluRay, and even then, I don’t think it likely. LPCM is a fall-back position - BluRay players can extract LPCM from a compressed (but lossless) format knowing that any TV or AV Receiver connected with HDMI will be able to play it (eARC is needed to then pass it to an external audio device like Arc because different wires are used for audio with HDMI-ARC as compared to HDMI). If LPCM is not sent, the TV must know how to decode the given compressed stream, or at least be able to pass it on to the audio device unaltered - neither of which is guaranteed. While it is mandatory that BluRay players support LPCM soundtracks, I don’t think you’ll find many movies with LPCM actually on the disk - they take up too much space best kept for 4K video.

You are largely correct in your findings, however. A UHD disk will often have multiple high quality soundtracks, as well as lesser 5.1 ones. How these are mixed is not only down to the original sound engineer who worked with the director, but also the BluRay authoring engineers. Which of these is used for streaming is up to the streaming service’s engineers and they may well adjust things themselves - I don’t know for sure.  The result of this is exactly what you found - the same movie on different services could easily be at differing volumes, even with the same audio format chosen.

One more point about LPCM is that it is what all audio players will use internally - it’s literally the only thing that the microchip responsible for converting digital audio into an analogue signal for amplification understands. Regardless of what format you are listening to, or what source it came from, it was converted to LPCM (or PCM for stereo) before you heard it so the source is always paramount when it comes to how loud it sounds - there’s nothing inherently quiet about LPCM, though if you are receiving it, it is often from a high-dynamic-range source and therefore not as loud as Dolby Digital or stereo PCM.

@ozthegweat 

Ah - I understand now. I was just looking in the app wondering where you had seen it. Yes, I presume that it would be mentioned there (not everything is mentioned, but enough people are interested that we’d include it in the notes).

I got typing faster than my brain was working. I meant PCM and Miltichannel PCM, not loseless. Sorry about that. I feel like going and borrowing a Bluray player and getting some disc's to test this. As far as streaming goes, it is amazing what happens to the same movie with multichannel PCM when it is moved from one service to another. I'm sure older movies on bluray also suffer from studio limitations at the time of filiming.

Hi @ozthegweat 

I’m not sure where you’re referring to in the app, but it would be listed in our Release notes for Sonos S2 page.

Hi @Missionsparta 

Multichannel PCM and LPCM are the same thing, as far as I am aware (and both are lossless); I can find references to McLPCM in my internal documentation. The terms are largely interchangeable.

The worst part of it all is that engineers who have never even met the director often remix soundtracks for DVDs and BluRays. Although it was video that was affected, this was illustrated by The Matrix movies - on DVD and VHS, the colour grading (green for in the Matrix, blue for the Real World) was exaggerated beyond the level the Wachowski’s ever wanted - it was only fixed with the UHD release. I sure the same happens with audio, only probably more so.

Im able to get titles to play in Multichannel PCM over streaming services. So not saying there isn't loseless multichannel PCM, but im getting some form of compressed version. But yeah, I think the different studios, different services, different manufacturing, etc all play major effect in what we are getting. I know it's just streaming, but listening to titles be shuffled from one service to anther and getting completely different results tell you that the human element 100% comes into play and I'm sure the same can happen with blurays.

Same here. 

​Hi @Flaku, 

Welcome to the Sonos community and thanks for reaching out to us. Let me share some information to help you out. 

LCPM ​is an uncompressed audio format that provides high-quality audio to our eARC supported home theater devices. It supports up to 8 channels (5.1 and 7.1 surrounds are the most common). Getting audio depends on the physical source device playing the content and the format or output must be set to one of our supported home theater audio formats. Some players and game consoles use DTS audio format which is not supported by Sonos. Some have the ability to transcode DTS into a format that Sonos supports, such as Dolby Digital 5.1. You may also check this article about unsupported audio on home theater speakers for reference.

To take a look at your Sonos system, it would be great if you can submit a diagnostic and include the confirmation number in your response. I'd appreciate it too if you can provide us the make and model of your TV so that we can look up the information.

If you need help with any other information, please be sure to let us know. We’ll wait for your reply.

I'm adding a me too as well. I would really like this issue fixed

Hi @Whistler 

I confess I didn’t really think of music BluRays - thanks for setting me straight!

I’ll see if I can get someone with an Arc to give that file a listen - thank you for the effort you obviously put in to do that.

Doesn’t seem like it. For now i am using the Dolby stream option. But agreed it needs to be fixed as this is embarrassing for a system that costs a fortune. 

Hi Corry, 

No problem!  Needless to say you need to play this on a device that does bitstream Passthrough and not for instance a Apple TV 4K that converts everything to LPCM by default to hear the difference between the tracks.

So for now is best to use DD+ 5.1 I assume(for playing)?

But who is at fault ,Sonos ,Sony ps5 or Sony tv, that is question?

Hmm 

Annoying ,will have to be patient now and just wait, I feel like a beta tester IMHO

This is an issue with The Arc I believe. Because the apple tv also treats the arc as a multichannel 7.1 and sends audio that way. Which results in low dialog and weird surround performance and even lipsync issues for me…

On the PS5, you can change your source to a AV reiceiver and force it to 5.1 multichannel which I believe fixes this.

But the Arc should tell the sources that it can only handle 5.1 not 7.1 not sure why we would ever get 7.1 onto the arc if it cant handle it and it doesnt seem to be downmixing it.

Currently I am using Apple TV 4K + Infuse. Which converts everything to LPCM which should be identical to the original source. I really would like the best possible quality I can get and this solution should in theory be a “one-that-does-it-all” solution. I used the Zidoo because I also want the best Atmos experience with Dolby TrueHD + Atmos, which the Apple TV 4K cannot do. (So much for that one-that-does-it-all solution right lol).  I have also tried the Nvidea Shield but did not really like it. I am more of a Apple eco-system guy. Thanks for your input, and maybe I have to reevaluate my setup in the near future ;)

Hi @bignicknicknick 

Your Arc will basically be playing what it is told to play - if LPCM sounds different to other formats (soft and muddy), it’s because your Apple TV (or TV) is delivering it that way. Different hardware is decoding whatever came before LPCM (it’s unlikely that the source media contained a LPCM track), and that must be the reason for things sounding differently.

If volume is the only difference, however, I can only suggest altering the volume with the controls.

I hope this helps.

I should clarify. My TV is a LG C9 with the latest updates. So it isn’t a TV issue. Unless it is a common issue amongst all TV’s which I doubt.