Linux PulseAudio - Combined output (dual audio): Still a bug in PulseAudio?
#1
I'd like to use a combined sink for Kodi (v17) on my HTPC (Intel J5005), running on Linux Mint 19.1.

My HTPC is connected by HDMI to my AVR.
I want to use Zone 2 on my AVR for stereo music but only analog input is supported therefore.

The description in the Kodi Wiki (PulseAudio - 4 Combined Output aka dual audio) is clear and it seems to be easy to activate dual audio.
Unfortunately there is a big limitation documented.
Quote:Downside: The dual audio sink will only output decoded audio, you cannot use it to have one slave doing AC3/DTS and the other PCM. If you use the combined sink for normal music you will realize that direct passthrough output for your movies won't be working anymore, too. This is a pulseaudio bug, cause the combine sink is not deconstructed fast enough internally while the passthrough opening is always exclusive. It will work however if your passthrough device is not part of the device combination.

I use the passthrough mode for digital codecs (AC3, EAC3, DTS, ...).
I'd like to have all supported audio formats (stereo and surround) on the HDMI port and stereo signals (mainly from FLAC files) also on my analog output (front speaker, lime-colored connector at the I/O panel at rear).
As I read the limitation this will not work and I will only get stereo signals on the HDMI port and the analog port. This will not be a proper solution for me.

As I can see, this limitation was documented in the Wiki in the version from 7 December 2014 (whereas in the version of 10 June 2014 it seemed to work like I'd like to have it).

Since this limitation was documented years ago, I'd like to know, if this limitation still exists (in Kodi 17) or if it will be fixed in Kodi 18.
As I can read, this is a bug in PulseAudio but I can't find a bug therefore in the PulseAudio Issues .

Currently I’m doing a workaround at my AVR where I don’t use Zone 2 but a Front A / Front B setting instead (and my HTPC is connected to the AVR only by HDMI).
However this is not a good solution for me because I always have to enter the setup of my AVR instead of using the comfortable Zone 2 feature and so it’s not independent for the Main Zone.
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#2
check out the audio profiles addon, I think it may handle what you want.  No dual sink issues
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#3
(2019-01-09, 05:43)disaacso Wrote: check out the audio profiles addon, I think it may handle what you want.
I'm not sure and I don't think so.
Even for me it's absolutely unclear, why I would need this add-on. Also the documentation doesn't give me any reason why I should use/need this add-on.
It's also not my goal to switch between audio-profiles manually.

Basically for me it's not a problem in Kodi which should be solved with an add-on.
AFAIK it has no impact if the underlying audio-subsystem doesn't support dual audio or analog output. In PulseAudio only HDMI-Output is configured for me and with the GUI it's only possible to configure one device.


It's also not so easy for me to test it, because I have to remove my HTPC and AVR from my rack and connect it by an appropriate cable. And first I have to buy a proper cable (3.5 mm phone connector to 2 x RCA).
 
(2019-01-09, 05:43)disaacso Wrote: No dual sink issues
I don't know to what this is related: To the add-on or to combined in PulseAudio (for Kodi) in general.
And then I don't know why this limitation is documented in the Wiki.
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#4
For me dual sink works nicely. I use Analog out from speakers + HDMI out to AVR and even a connected bluetooth headset additionally.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#5
(2019-01-09, 20:00)fritsch Wrote: For me dual sink works nicely. I use Analog out from speakers + HDMI out to AVR and even a connected bluetooth headset additionally.
Okay, this sounds good!
And you also have audio output on all ports - as far as they support the respective sound format?

Can you tell me, which Linux distribution and Kodi version you use?
If already v18: Did it work for you also von v17?
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#6
Also a pain point to a possible solution with the add-on Audio Profiles might be, that I use Kore (the Android app for Kodi) to control it in Zone 2.
I suspect I cannot switch the audio profiles with this app but this would be very important for me, when lying in bed, where I use Zone 2 )and my HTPC runs head-less).
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#7
(2019-01-09, 20:36)NeroRome Wrote:
(2019-01-09, 20:00)fritsch Wrote: For me dual sink works nicely. I use Analog out from speakers + HDMI out to AVR and even a connected bluetooth headset additionally.
Okay, this sounds good!
And you also have audio output on all ports - as far as they support the respective sound format?

Can you tell me, which Linux distribution and Kodi version you use?
If already v18: Did it work for you also von v17? 
 Yes - it worked also. It's obviously clear that pulseaudio won't do "AC3" to one sink and "PCM" to the other. So I just feed decoded data.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#8
Are you only listening to music on zone 2, i.e. not in your main location, if so you can set up the audio profile to automatically switch to the analog output when listening to music.  You can also set up a button to switch profiles with a script, both cases are detailed in the addons documentation.  I never had great success using a combined sink with pulse audio, sync issues with video.
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#9
The sync stuff I "think" I had fixed some years ago - but I can retest when time permits.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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PulseAudio - Combined output (dual audio): Still a bug in PulseAudio?0