[alsa-devel] Surround sound not working on ALC887 based motherboard

[Raymond Yau]

2014/1/15 Olivier Crête <olivier.crete at ocrete.ca>

> Hi,
>
>
> > >         I have a Asus P5G41T-M LX Plus motherboard which is ICH7 +
> > >         Realtek
> > >         ALC887-VD, alsa only lets me access the first 2 channels
> > >         (stereo), but
> > >         not the 6 other ones. It works fine in Windows.
> > >
> > >         Trying to run this after killing pulseaudio fails:
> > >
> > >         $ aplay -D surround40:0 -f S16_LE -r 44100 -c 4 /dev/zero -v
> > >         Playing raw data '/dev/zero' : Signed 16 bit Little Endian,
> > >         Rate 44100 Hz, Channels 4
> > >         aplay: set_params:1239: Channels count non available
> > >
> > >
> > >         Output from alsa-info:
> > >
> http://www.alsa-project.org/db/?f=fe378d28f0dbb5a427b005d20866a762fd37d31a
> >
> > >
> > > post output of pactl list or pulseaudio verbose log
> >
> > http://www.ocrete.ca/surround/pactl-list.txt
> > http://www.ocrete.ca/surround/pulseaudio-vv.txt
> >
> > > you have to change channel mode from 2ch to 6ch to retask the input
> > > jacks as output if your motherboard only have three audio jacks at
> > > rear panel
> >
> > How would one do that ? Pulseaudio only offers Stereo profiles.
>

amixer -c0 set "Channel Mode" "6ch"

>
> > do you mean pulseaudio cannot probe the surroun40 or surround51
> > profile ?
>
> Yes, but I can't use it with aplay even without pulseaudio running.
>
> > Simple mixer control 'Channel Mode',0
> >   Capabilities: enum
> >   Items: '2ch' '4ch' '6ch'
> >   Item0: '2ch'
>
>

> For some reason didn't get your last email, but I saw I saw it on the
> archive.. Thanks for your solution, it worked! Definitely something
> PulseAudio should expose better.


do it really work since rear mic become active port even when it had been
retasked as output ?

Ports:
		analog-input-front-mic: Front Microphone (priority: 8500, not available)
		analog-input-rear-mic: Rear Microphone (priority: 8200, available)
		analog-input-linein: Line In (priority: 8100, available)
	Active Port: analog-input-rear-mic