XBMC surround channel mix up (only xbmc)
#16
I went into the pulseaudio channel and talked with FordPrefect, the pulseaudio maintainer to have a look at the xbmc code. It is perfectly fine and we are doing it like the PA devs want it to be done. E.g. providing a channel map with the annotated positions. The rest needs to be done by pulseaudio itself.

So - every dumpfixing (like with the patch above) is not what we should need.

Here is what Ford_Prefect wants you to do:
Quote:12:13 < Ford_Prefect> If the user has the gnome/ubuntu sound panel (which is
the same), the user could run the speaker test thing to
make sure PA mappings match speaker positions
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#17
I think you are correct and that it's something in PA. Thanks for sorting that out.

I will (I noticed I was running behind) upgrade to Mint 17 (≃Ubuntu 14.04 LTS) and in the meanwhile reset all PA settings and report back. As far as I know I've only changed the sample size/rate and default number of channels, but that doesn't mean PA isn't doing something strange...?

Edit: No, I didn't seem to have gnome-sound-applet but I kept searching for where I could test the speakers using only PA. Thanks for that too.
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#18
Well, nope.

1. nothing changed with the default pulseaudio config files with a fresh Mint 17 upgrade (I removed and forced in new config files from the package)
2. gnome-sound-applet gives the right sound in the right channels

I'm still confused here.
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#19
Ok, now I will change this to a bug report. :p

I had some odd sound artifacts before so I had changed the audio settings to fixed/192kHz.

Changing the audio settings to 5.0 fixed the problem, but no subwoofer channel at all (I guess it's not mixed in from AC3/wmv to 5.0?).

Changing them back to optimized or best match fixed the problem.

Changing them to fixed/192kHz or fixed/96kHz repeats the problem.

Anything I can help with to nail down this problem?

(Edit: I can repeat the sound artifact. On a stereo - or possible mono - video, the sound gets excessively echo-y and in all channels if I don't use fixed. On a 5.1 video it's all fine. So to get decent sound I need to use fixed. I will upgrade to 13.2/14.0 again and see if that's still the case. No, I don't use stereo upmix and the sound is sent as 5.1 to the receiver. Edit 2: This seems to be due to pulseaudio enable-remixing default to yes, so not an XBMC problem.)
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#20
Nope sub is never mixed into anything - think of 20 hz in some little rear speakers.

Please post a logfile with "working" config and with "non working" config.
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#21
working
non working
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#22
Sadly not a debug log - I cannot see a single difference :-) (but it's already late)
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#23
(2014-08-20, 21:57)fritsch Wrote: Sadly not a debug log - I cannot see a single difference :-) (but it's already late)

Doh, yes. I'll redo them.

Edit: Fixed, same URLs as above with addition:

nonworking to working (settings changed and video played first nonworking then perfectly)

Also, the channel order is changed:
working - pavucontrol screenshot
nonworking
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#24
Okay, so in summary - it works always with

Best Match and Optimized and 5.1 settings

but it does not work with Fixed and 5.1 settings - the only way Fixed is working is by settings Speakers to 5.0

Is that correct?

Quote:Non working: Channel Layout: FL,FR,FC,BL,BR,LFE

Quote:working: FL,FR,FC,LFE,BL,BR

I will ask my Audio Engine colleague FernetMenta if he has an idea - concerning the fixed setting. As in fixed mode the device is opened exactly ones at the beginning I think that some "mapping" that the engine needs to do when some stream changes is not adjusted.

Logfiles:
http://www.mirar.org/xbmc.debug.nonworking.log http://www.mirar.org/xbmc.nonworking.png
http://www.mirar.org/xbmc.debug.working.log http://www.mirar.org/xbmc.working.png

On last question from me: When you play with the wrong mapping (e.g. Fixed 5.1) and go to pavucontrol and here reduce the volume of LFE or Center channel to zero (in the xbmc stream) - then go over to those speakers - are they nearly silent now? I want to find out if the "PA labels" are correct.

Image
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#25
(2014-08-20, 22:35)fritsch Wrote: Okay, so in summary - it works always with

Best Match and Optimized and 5.1 settings


but it does not work with Fixed and 5.1 settings - the only way Fixed is working is by settings Speakers to 5.0

Correct.

(2014-08-20, 22:35)fritsch Wrote: On last question from me: When you play with the wrong mapping (e.g. Fixed 5.1) and go to pavucontrol and here reduce the volume of LFE or Center channel to zero (in the xbmc stream) - then go over to those speakers - are they nearly silent now? I want to find out if the "PA labels" are correct.

Good call.

Turning off "rear left": no subwoofer buzz
Turning off "rear right": no sound from rear left speaker
Turning off "subwoofer": no sound from rear right speaker
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#26
The latter is bad. It's a pulseaudio bug we trigger by accident, but I am quite sure I know where it is coming from :-)

If you look at default ALSA mappings, you see that speakers are always in pairs: FL, FR, center, lfe, BL, BR

in that case pulse or alsa or the mapping in between guesses the channel after Center must be LFE and and the 5th channel is BL and 6th channel is BR ... please file a bug with pulseaudio on their bugtracker - we sadly cannot really workaround this as pulse is not working as expected.

Therefore you get BL in the Sub and LFE in rear
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#27
Here is a patch, please apply that on top of xbmc master branch and give it a try please

http://paste.ubuntu.com/8103655/

Best regards
Peter
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#28
I pushed it to my master branch, you can build it by doing:

Code:
sudo apt-get build-dep xbmc
sudo apt-get install libxslt-dev
git clone https://github.com/fritsch/xbmc.git
cd xbmc
./bootstrap
./configure --disable-debug
make -j5

Now you can do sudo make install or run it from that xbmc directory (./xbmc.bin) - it will install to /usr/local - make sure to start the correct version afterwards.

Best regards
Peter
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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#29
I can confirm the sound works with fixed in the git version (Git:2014-08-21-33
26758-dirty) while the exact same setup doesn't work in 13.2 final (Git:0f3db05).

Not sure how to file a bug report since I don't know how XBMC is handling the sound well enough. :p
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#30
please paste the latest commit you have in here:

git show

as I added some more things.
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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XBMC surround channel mix up (only xbmc)0