Hi,
I recall that after we got the LPCM update for the Arc, it was noticed by the community that 7.1 LPCM tracks were not being properly downmixed to 5.1 and the end result were missing channels. Is that still an issue today? If I have the Sonos app reporting LPCM 7.1 does that mean I will be missing 2 channels when outputing it to Arc, 2x Ones and a Sub?
Thanks
+18
Hi
I guess we misunderstood that tweet then. At the same time I also didn't think the sonos arc had that many bugs/issues that something needs to be pushed down a list for going on 2 years since the tweet.
We don’t have software engineers that only work on the Arc. To be honest, I have no idea how the team is divided, if at all. I think it’s a fair assumption, however, that most of the work they do in regards to fixing issues is done on a priority basis. As 7.1 downmixing is not seen as an issue, but as an unimplemented future feature, its priority is low. This thread, here on this forum, may be bumping it up the queue as we speak.
Whether it is an actual issue or not, before the LPCM update on Sonos, the sonos app reported as receiving DD 5.1 fine (apart from DTS, my LG does not support that). So it’s the sonos lpcm update that altered something.
As HDMI is a connection that allows control communication between the devices, I think what’s happening is that since the update, when the Arc is queried as to what formats it can play, it now replies with an answer that includes LPCM. That makes either your TV or source device change it’s opinion about which audio stream should be played (the best quality stream supported by all the devices would be chosen - that used to be DD 5.1).
It’s possible that your source/TV is remapping (or up-mixing) a 5.1 LPCM track to a 7.1 LPCM track. If the two extra channels are silent, or duplicates of other channels, then it won’t really matter that the Sonos app reports 7.1. As long as you get the intended 5.1 channels in the correct places, that is what counts.
I hope this helps.
Hi Everyone,
Well, this is embarrassing!
After some investigation, I’ve found that downmixing of 7.1 channel LPCM to 5.1 channel LPCM was indeed implemented on the Arc as a feature last year, but our literature wasn’t properly updated to reflect the change.
To be clear, the Arc does downmix 7.1 LPCM to 5.1, has done for some time, and we are working on updating our documentation to reflect the fact. Beam (Gen 2) has always supported LPCM and has always downmixed.
Thank you all for pointing this out to me so we can now make sure that this information becomes public. I’m sorry for the unnecessary confusion. I’ll post this in multiple threads.
This other issue with LG TVs is unrelated, but we’d very much like to get on top of it. We’ve requested the investigation of LPCM channels being played from the wrong speakers when an LG TV is involved, specifically when 7.1 channels are reported, and we will reach out to LG with details once we’ve gathered some solid evidence for them. Therefore, we’d very much appreciate it if anyone affected by this specific issue would visit this new thread I’ve made for gathering some details. Thank you.
Thank you very much for clarifying this here and in other posts. As a request going forward, I really do wish Sonos would reconsider their practice of generically describing bug fixes as only “Bug fixes and performance enhancements” in their release notes when it includes significant fixes that have been raised in multiple posts here over several months. It would go a long way to help avoid confusion like this in the future.
I bought the Sonos ARC, sub and symfonisk frames for rear duties just a couple of days ago and although I am happy with the sound I am having issues regarding DTS Blu-ray. I have set my Blu-ray player to output DTS master audio as LPCM but the app shows PCM 7.1 not 5.1. Does this mean the ARC is ignoring 2 channels and not playing audio correctly? I have a Sony a80j OLED TV which is set to passthrough and have had zero issues with my previous Samsung q950t soundbar connected. I am not new to home theatre and have had various systems throughout the years from full atmos installs to various HIFI separates and sound-bars so I know it’s not user error or setting problems. I was under the impression I could get DTS Master audio via LPCM without issue but now I’m not so sure. Any ideas?
There is a known LPCM 7.1 to 5.1 down mixing issue with the Arc. Sonos is aware of this and is working on fixing the issue. Some people have reported they can clearly hear two channels missing from the surround audio, but I can’t tell the difference. I have tested the surround channels with a DTS 7.1 Sound Check on a DTS demo disc and all four surround channels play out of my two surround speakers correctly. But I am also using an HDFury Arcana which might be the reason why I don’t seem to be experiencing the down mixing problem.
depends how you are testing it too. When I found this problem I was testing it using a test disc that plays isolated beeping sounds through each channel one by one (it's a calibration tool so you can make sure the channels work and the volume is correct) and two of the channels were clearly not working, the disc was playing audio but the Sonos speakers made no sound. I also tested it a second time using a game - games also works well for testing because you can make a static sound come out of any channel you want by moving around.
Testing this problem using a movie or music or anything that you can't control won't work because you have no idea what you're supposed to hear and just accept it as fact. Testing surround audio in a movie or music is only possible if you have a 2nd system to compare against
+18
Hi
So I do appreciate you responding but the issue here is that nobody is sending a 7.1 signal and worrying about whether it will play or whether Sonos supports it. I am not seeing anybody asking for 7.1 support to be added as a feature in any of the many threads discussing this issue as what would be the point on a system that physically tops out at 5.1?
The issues are all associated with playing back 5.1 tracks that are being reported as 7.1 in the sonos app. For me this happens with an Apple TV 4K and a PS5. Either the TV is converting 5.1 to 7.1 incorrectly (in my case an LG CX), or the TV is sending the correct 5.1 track but the wrong metadata to the Beam, or the Beam is incorrectly reporting received 5.1 tracks as 7.1 in the app.
I think you should read the first post on this thread again. 7.1 downmixing to 5.1 is the topic of this thread, regardless of what anyone else has been saying. The post from
The point of supporting 7.1 on a system that only has 5.1 (apart from when it’s 5.1.2) is that instead of throwing away channels to play the stream, channels are amalgamated instead (down-mixed). Side-channel effects would, presumably, be mixed to both front and rear channels on that side, for example.
I’d be happy to submit diagnostics etc if it would help but I think there is a bug here somewhere, not a missing feature.
No bugs. If you play a 5.1 track and it arrives at the Arc as a 7.1 track, then, as you have said, your source device or TV has either up-mixed it to 7.1 or has changed the descriptor on the stream for some reason (I can’t think of any valid reasons to do this). Either way, it’s not something we, Sonos, can address.
I recommend you get in touch with LG or Sony support.
sonos does not support 7.1, that is correct and we know it
But other issue is that system is not able to properly downmix LPCM 7.1 to 5.1
tweet from sonos CEO over a year go.
From my understanding of EDID, the ARC must be reporting itself as 7.1 capable to the TV, then the TV passes that down the line (Xbox, PS, Blu-ray player etc?), or the TV is misinterpreting the EDID data?.
Seems Sonos have problems now with 5.1 PCM, maybe due to tying to support 7.1 🤔.
I bought the Sonos ARC, sub and symfonisk frames for rear duties just a couple of days ago and although I am happy with the sound I am having issues regarding DTS Blu-ray. I have set my Blu-ray player to output DTS master audio as LPCM but the app shows PCM 7.1 not 5.1. Does this mean the ARC is ignoring 2 channels and not playing audio correctly? I have a Sony a80j OLED TV which is set to passthrough and have had zero issues with my previous Samsung q950t soundbar connected. I am not new to home theatre and have had various systems throughout the years from full atmos installs to various HIFI separates and sound-bars so I know it’s not user error or setting problems. I was under the impression I could get DTS Master audio via LPCM without issue but now I’m not so sure. Any ideas?
There is a known LPCM 7.1 to 5.1 down mixing issue with the Arc. Sonos is aware of this and is working on fixing the issue. Some people have reported they can clearly hear two channels missing from the surround audio, but I can’t tell the difference. I have tested the surround channels with a DTS 7.1 Sound Check on a DTS demo disc and all four surround channels play out of my two surround speakers correctly. But I am also using an HDFury Arcana which might be the reason why I don’t seem to be experiencing the down mixing problem.
I think this is/was an issue with some LG CX TV’s, see this thread for additional info:
The above link runs into a slightly longer thread, which seems to infer that some devices send LPCM 7.1 audio ‘through’ the LG CX TV if it’s HDMI sound-out is set to pass-through, and that Sonos plan to possibly downmix the channels to 5.1 in a future update (no information about when that might happen) - at least that’s how the thread reads to me at a quick glance.
Maybe changing the audio-out settings on the A/V sending device, or changing the TV HDMI Digital Sound Out to ‘Auto’ (instead of pass-through) to let the TV process the audio before it gets to the Sonos HT, will help to fix the issue in the meantime, if it is perhaps causing you an issue.
Is that still an issue today? If I have the Sonos app reporting LPCM 7.1 does that mean I will be missing 2 channels when outputing it to Arc, 2x Ones and a Sub?
Thanks
Yes this is still an issue and an infuriating one at that. Sonos has not yet announced the downmix feature and LG are completely silent on the issue which is entirely unsurprising.
I bought the Sonos ARC, sub and symfonisk frames for rear duties just a couple of days ago and although I am happy with the sound I am having issues regarding DTS Blu-ray. I have set my Blu-ray player to output DTS master audio as LPCM but the app shows PCM 7.1 not 5.1. Does this mean the ARC is ignoring 2 channels and not playing audio correctly? I have a Sony a80j OLED TV which is set to passthrough and have had zero issues with my previous Samsung q950t soundbar connected. I am not new to home theatre and have had various systems throughout the years from full atmos installs to various HIFI separates and sound-bars so I know it’s not user error or setting problems. I was under the impression I could get DTS Master audio via LPCM without issue but now I’m not so sure. Any ideas?
There is a known LPCM 7.1 to 5.1 down mixing issue with the Arc. Sonos is aware of this and is working on fixing the issue. Some people have reported they can clearly hear two channels missing from the surround audio, but I can’t tell the difference. I have tested the surround channels with a DTS 7.1 Sound Check on a DTS demo disc and all four surround channels play out of my two surround speakers correctly. But I am also using an HDFury Arcana which might be the reason why I don’t seem to be experiencing the down mixing problem.
Are they?
Sorry to quote an old post, but this issue is ancient now, its quite laughable that they said they were working on it, which is well over a year ago. They dont even acknowledge the issue or respond to posts on the subject anymore to give an update.
Issue or no issue, they should respond.
Is this a problem for the LG G1? Are we supposed to keep the TV audio set to auto still? If my source file is a TrueHD 7.1 Atmos remux, do I still want my Sonos App to show Multichannel PCM 5.1?
+18
Hi
Are they?
Sorry to quote an old post, but this issue is ancient now, its quite laughable that they said they were working on it, which is well over a year ago. They dont even acknowledge the issue or respond to posts on the subject anymore to give an update.
Issue or no issue, they should respond.
Sonos does not currently support 7.1 channel McLPCM audio, though, as you see above, some users report experiencing no problems with it.
The official line is, “this is a feature we are currently working on, however; we do not have any further information to share with you at this time. Rest assured, we will address this in a forthcoming update.”
Once we have made our position clear - that we have never supported this format, therefore it not working isn’t an issue or a bug, but a forth-coming feature that we haven’t yet released or advertised - it seems needless to repeatedly answer all references to it. When we do release the feature, we’ll update the relevant threads on the forum - closed or not. Incidentally, I don’t think “working on” literally means there’s someone coding away at it right now, but that it is in a list of work that needs to be done and is quite likely to be repeatedly pushed down that list by actual bugs/issues that show up, or by upcoming projects/features that require a lot of concerted effort.
Hi
Are they?
Sorry to quote an old post, but this issue is ancient now, its quite laughable that they said they were working on it, which is well over a year ago. They dont even acknowledge the issue or respond to posts on the subject anymore to give an update.
Issue or no issue, they should respond.
Sonos does not currently support 7.1 channel McLPCM audio, though, as you see above, some users report experiencing no problems with it.
The official line is, “this is a feature we are currently working on, however; we do not have any further information to share with you at this time. Rest assured, we will address this in a forthcoming update.”
Once we have made our position clear - that we have never supported this format, therefore it not working isn’t an issue or a bug, but a forth-coming feature that we haven’t yet released or advertised - it seems needless to repeatedly answer all references to it. When we do release the feature, we’ll update the relevant threads on the forum - closed or not. Incidentally, I don’t think “working on” literally means there’s someone coding away at it right now, but that it is in a list of work that needs to be done and is quite likely to be repeatedly pushed down that list by actual bugs/issues that show up, or by upcoming projects/features that require a lot of concerted effort.
If Sonos doesn’t support 7.1 LPCM why/how does it report it in the app? I don’t think anybody is deliberately trying to send an unsupported format to the speaker, or waiting for it to be added as a feature. Rather it appears that the speaker is either asking for it incorrectly, or it is being sent incorrectly over eARC by LG OLED TVs. Either way this is a problem not a missing feature albeit maybe not of Sonos making. The frustration in these threads is more to do with the lack of clarity and uncertainty of whether it is impacting the sound in any way. I’m inclined to suspect that a hardware issue has been found hence the silence for so long and the repositioning of this as a feature but would be happy to be corrected.
+18
Hi
If Sonos doesn’t support 7.1 LPCM why/how does it report it in the app?
I think you’re confusing “support” with “play” and “recognise”. What we mean by “not supporting”, in this instance, is that if it doesn’t work, and you call our technical support team to try and get it working, we won’t be able to assist. Not out of spite, or hardware issues, but because the software to downmix 7.1 to 5.1 hasn’t yet been fully written/tested/implemented.
The frustration in these threads is more to do with the lack of clarity and uncertainty of whether it is impacting the sound in any way. I’m inclined to suspect that a hardware issue has been found hence the silence for so long and the repositioning of this as a feature but would be happy to be corrected.
We cannot tell you that the 7.1 stream will be impacted in a certain way if it has not been fully explored and tested. No information is often (if not always) better than wrong information. We have not mentioned 7.1 support in any way, other than to respond to direct customer queries. The acknowledgement that we will be supporting 7.1 at all in the future is, frankly, more information than we usually put out about up-coming features.
If a digital audio stream can be transported to an audio device quickly enough, then the only thing that would get in the way of it playing is lack of software, and CPU power to run the software (and LPCM doesn’t take much). For example, all our Home Theatre products - even those that are discontinued - recently gained the ability to play DTS streams, simply by us adding software to let them do so.
I hope this helps.
Is this a problem for the LG G1? Are we supposed to keep the TV audio set to auto still? If my source file is a TrueHD 7.1 Atmos remux, do I still want my Sonos App to show Multichannel PCM 5.1?
The Sonos app should show the Dolby Atmos logo if you are playing a Dolby TrueHD/Atmos source. Be sure the HDMI Input Format setting on the TV is set to Bitstream and eARC is enabled. If it is a Blu-ray disc, set the player’s settings to Bitstream too and turn off Secondary Audio.
Hi
If Sonos doesn’t support 7.1 LPCM why/how does it report it in the app?
I think you’re confusing “support” with “play” and “recognise”. What we mean by “not supporting”, in this instance, is that if it doesn’t work, and you call our technical support team to try and get it working, we won’t be able to assist. Not out of spite, or hardware issues, but because the software to downmix 7.1 to 5.1 hasn’t yet been fully written/tested/implemented.
The frustration in these threads is more to do with the lack of clarity and uncertainty of whether it is impacting the sound in any way. I’m inclined to suspect that a hardware issue has been found hence the silence for so long and the repositioning of this as a feature but would be happy to be corrected.
We cannot tell you that the 7.1 stream will be impacted in a certain way if it has not been fully explored and tested. No information is often (if not always) better than wrong information. We have not mentioned 7.1 support in any way, other than to respond to direct customer queries. The acknowledgement that we will be supporting 7.1 at all in the future is, frankly, more information than we usually put out about up-coming features.
If a digital audio stream can be transported to an audio device quickly enough, then the only thing that would get in the way of it playing is lack of software, and CPU power to run the software (and LPCM doesn’t take much). For example, all our Home Theatre products - even those that are discontinued - recently gained the ability to play DTS streams, simply by us adding software to let them do so.
I hope this helps.
So I do appreciate you responding but the issue here is that nobody is sending a 7.1 signal and worrying about whether it will play or whether Sonos supports it. I am not seeing anybody asking for 7.1 support to be added as a feature in any of the many threads discussing this issue as what would be the point on a system that physically tops out at 5.1?
The issues are all associated with playing back 5.1 tracks that are being reported as 7.1 in the sonos app. For me this happens with an Apple TV 4K and a PS5. Either the TV is converting 5.1 to 7.1 incorrectly (in my case an LG CX), or the TV is sending the correct 5.1 track but the wrong metadata to the Beam, or the Beam is incorrectly reporting received 5.1 tracks as 7.1 in the app.
I’d be happy to submit diagnostics etc if it would help but I think there is a bug here somewhere, not a missing feature.
The Sonos app should show the Dolby Atmos logo if you are playing a Dolby TrueHD/Atmos source. Be sure the HDMI Input Format setting on the TV is set to Bitstream and eARC is enabled. If it is a Blu-ray disc, set the player’s settings to Bitstream too and turn off Secondary Audio.
This is on a 2021 Apple TV 4k with Plex. I’ve tried the Plex app and with Infuse 7. The TV is set to Bitstream and eARC is enabled. I’ve tried with the TV set to both passthrough and auto. Auto show’s multipath PCM 5.1 on the Sonos app and passthrough shows multipath 7.1. It’s the same with any other source file I try irregardless of the sound format (unless it’s a stereo 2.0 source).
Hi
So I do appreciate you responding but the issue here is that nobody is sending a 7.1 signal and worrying about whether it will play or whether Sonos supports it. I am not seeing anybody asking for 7.1 support to be added as a feature in any of the many threads discussing this issue as what would be the point on a system that physically tops out at 5.1?
The issues are all associated with playing back 5.1 tracks that are being reported as 7.1 in the sonos app. For me this happens with an Apple TV 4K and a PS5. Either the TV is converting 5.1 to 7.1 incorrectly (in my case an LG CX), or the TV is sending the correct 5.1 track but the wrong metadata to the Beam, or the Beam is incorrectly reporting received 5.1 tracks as 7.1 in the app.
I think you should read the first post on this thread again. 7.1 downmixing to 5.1 is the topic of this thread, regardless of what anyone else has been saying. The post from
The point of supporting 7.1 on a system that only has 5.1 (apart from when it’s 5.1.2) is that instead of throwing away channels to play the stream, channels are amalgamated instead (down-mixed). Side-channel effects would, presumably, be mixed to both front and rear channels on that side, for example.
I’d be happy to submit diagnostics etc if it would help but I think there is a bug here somewhere, not a missing feature.
No bugs. If you play a 5.1 track and it arrives at the Arc as a 7.1 track, then, as you have said, your source device or TV has either up-mixed it to 7.1 or has changed the descriptor on the stream for some reason (I can’t think of any valid reasons to do this). Either way, it’s not something we, Sonos, can address.
I recommend you get in touch with LG or Sony support.
I think you should read the posts on this thread again and the many others by the person you replied to discussing the exact issue I outlined. Your reply seems unnecessarily dismissive and condescending. I and many others are only asking for some feedback on an issue that I acknowledged may not be on Sonos but I suspect probably is to some extent as it spans multiple hardware sources from different manufacturers.
This is on a 2021 Apple TV 4k with Plex. I’ve tried the Plex app and with Infuse 7. The TV is set to Bitstream and eARC is enabled. I’ve tried with the TV set to both passthrough and auto. Auto show’s multipath PCM 5.1 on the Sonos app and passthrough shows multipath 7.1. It’s the same with any other source file I try regardless of the sound format (unless it’s a stereo 2.0 source).
The Apple TV 4K doesn’t support Dolby TrueHD audio. You need an Nvidia Shield.
He is saying that but has no basis for it - all anyone is asking for is a little investigation from Sonos to confirm either way. The pairing of Sonos soundbars with LG OLEDs must be much more common as a proportion of Sonos customers than LG customers.
He is saying that but has no basis for it - all anyone is asking for is a little investigation from Sonos to confirm either way. The pairing of Sonos soundbars with LG OLEDs must be much more common as a proportion of Sonos customers than LG customers.
Even though the Sonos app is reporting “Multichannel PCM 7.1”, do you actually hear any audio loss from the surround channels?
The Apple TV 4K doesn’t support Dolby TrueHD audio. You need an Nvidia Shield.
So since the Apple TV converts the TrueHD audio, do I want it to be Multichannel 7.1 or 5.1 on the Sonos app? Is the 7.1 problematic on the LG G1 or was that problem just with the LG CX TV’s?
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