ALSA 5.1 Sound problem...

Compl33t · 2006-12-10 13:50:46

I'm using mpd (Music Player Deamon) at the moment to listen to my music collection, and although ALSA works without a hitch, I wanted to have sound on all my speakers for normal stereo sources.

In my ~/.asoundrc file I added add the following (as per instruction on the ALSA website)

pcm.duplicate {
type plug
slave.pcm "surround51"
slave.channels 6
route_policy duplicate
}

After that I set the ALSA device used for mpd to duplicate.

For mpd it's in /etc/mpd.conf under the audio_ouput section.
I added

device "duplicate"

Although this works, it seems to mess up the hardware mixing on my sound card (an AC97 variant). If I use the normal "surround51″ device, all is well.

Any ideas how I, or if, I can solve this?

aquila_deus · 2006-12-11 12:02:03

Compl33t wrote:

I'm using mpd (Music Player Deamon) at the moment to listen to my music collection, and although ALSA works without a hitch, I wanted to have sound on all my speakers for normal stereo sources.
In my ~/.asoundrc file I added add the following (as per instruction on the ALSA website)
pcm.duplicate {
type plug
slave.pcm "surround51"
slave.channels 6
route_policy duplicate
}
After that I set the ALSA device used for mpd to duplicate.
For mpd it's in /etc/mpd.conf under the audio_ouput section.
I added
device "duplicate"
Although this works, it seems to mess up the hardware mixing on my sound card (an AC97 variant). If I use the normal "surround51″ device, all is well.
Any ideas how I, or if, I can solve this?

Are you using VIA8237 chip? I got the problem too. The "surround" sound occupies hardware-mixing channels and mic/line-in ports.

You can solve the problem by using oss2jack. But surround sound would still disable mic/line-in.

Compl33t · 2006-12-11 22:20:07

aquila_deus wrote:

Are you using VIA8237 chip? I got the problem too. The "surround" sound occupies hardware-mixing channels and mic/line-in ports.
You can solve the problem by using oss2jack. But surround sound would still disable mic/line-in.

Not sure of the exact revision, but it definitely is a VIA82xx chip. I thought it would be something along the line of all the channels being used.

Hmm, I don't mind having the mic/line-in disabled. I'll look into oss2jack.

Thanks!

Compl33t · 2006-12-22 16:29:51

I've found the solution. Thought I'd share.

First things first, make sure you have JACK installed. Then, edit your ~/.asoundrc file to look like this

ctl.jack51 {
    type hw
    card 0
}
pcm.jack51 {
    # "asym" allows for different
    # handling of in/out devices
    type asym
    playback.pcm {
    # route for mmap workaround
    type plug
    slave.pcm "surround51"
    slave.channels 6
    route_policy duplicate
    }
    capture.pcm {
        # 2 channels only
        type hw
        card 0
    }
}

Then, start JACK with

jackd -d alsa -d jack51

(Loading JACK at startup can be done in a variety of ways, depending on how you do things)

I had trouble starting it up as a regular user, but that can be fixed by editing /etc/security/limits.conf (as described in the wiki).

It's nice to have qjackctl installed to control JACK from your desktop environment.

pacman -S qjackctl

If your app supports JACK output, you're good to go! Simply set it to use JACK.

For MPD, I had to install the SVN 4125 trunk. Download the PKGBUILD and simply edit the version to the newest SVN build (check this on mpd's site). The 4125 release has support for JACK output.

Then, in /etc/mpd.conf, use this

audio_output {
                                type "jack"
                                name "mpd"

 }

Et voila! Surround sound with mixing.

Richtfest · 2006-12-24 14:40:49

I have the same problem, my 5.1 system dosen't work. I have build and edit my ~/.asoundrc und run Jack as Compl33t said

jackd -d alsa -d jack51

I have open xmms and play some mp3's but i get no sound.
[My sound card: Soundstorm/Dolby Digital]

Arch Linux

#1 2006-12-10 13:50:46

ALSA 5.1 Sound problem...

#2 2006-12-11 12:02:03

Re: ALSA 5.1 Sound problem...

#3 2006-12-11 22:20:07

Re: ALSA 5.1 Sound problem...

#4 2006-12-22 16:29:51

Re: ALSA 5.1 Sound problem...

#5 2006-12-24 14:40:49

Re: ALSA 5.1 Sound problem...

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