alsa or VLC bug ?

[sluke]

Hi,

I have a problem when I play 5.1 audio files in VLC. But I don't know if it's a problem about VLC alsa...
So when I play a 5.1 audio file in VLC (with Audio -> Audio Device -> 5.1), channels are blended :

"sound" --> result

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"Front Left" --> OK "Front Right" --> OK "Center" --> Side Left "Side Right" --> LFE "Side Left" --> Center "LFE" --> Side Right

See the log of VLC :

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VLC media player 1.1.12 The Luggage (revision exported) Blocked: call to unsetenv("DBUS_ACTIVATION_ADDRESS") Blocked: call to unsetenv("DBUS_ACTIVATION_BUS_TYPE") [0xb0c150] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface. Blocked: call to setlocale(6, "") Warning: call to srand(1322340469) Warning: call to rand() Blocked: call to setlocale(6, "") (process:18539): Gtk-WARNING **: Locale not supported by C library. Using the fallback 'C' locale. Warning: call to rand() Warning: call to rand() Warning: call to rand() Warning: call to rand() [0x7fca34013940] alsa audio output error: unable to set stream sample size and word order (Invalid argument) [0x7fca34013940] pulse audio output error: cannot connect to server: Connection refused

These lines appear only when I select 5.1 in VLC menu. By default, VLC selects stereo :

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[0x7fca34013940] alsa audio output error: unable to set stream sample size and word order (Invalid argument) [0x7fca34013940] pulse audio output error: cannot connect to server: Connection refused

"speaker-test -c 6 -l 1 -t wav" command => All channels are OK :

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speaker-test 1.0.24.2 Playback device is default Stream parameters are 48000Hz, S16_LE, 6 channels WAV file(s) Rate set to 48000Hz (requested 48000Hz) Buffer size range from 8 to 10920 Period size range from 4 to 5460 Using max buffer size 10920 Periods = 4 was set period_size = 2188 was set buffer_size = 10920 0 - Front Left 4 - Center 1 - Front Right 3 - Rear Right 2 - Rear Left 5 - LFE Time per period = 8.433966

An other information, my system is a debian Wheezy (amd64) :

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ii libvlc5 1.1.12-3 multimedia player and streamer library ii libvlccore4 1.1.12-3 base library for VLC and its modules ii vlc 1.1.12-3 multimedia player and streamer ii vlc-data 1.1.12-3 Common data for VLC ii vlc-nox 1.1.12-3 multimedia player and streamer (without X support) ii vlc-plugin-notify 1.1.12-3 LibNotify plugin for VLC ii vlc-plugin-pulse 1.1.12-3 PulseAudio plugin for VLC ii alsa-base 1.0.23+dfsg-4 ALSA driver configuration files ii alsa-utils 1.0.24.2-4 Utilities for configuring and using ALSA

.asoundrc file :

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pcm.!default { type plug slave ice1724_S32_LE; } pcm.duplicate { type plug slave.pcm "surround51" slave.channels 6 route_policy duplicate } pcm_slave.ice1724_S32_LE { pcm surround51; format S32_LE; }

5.1 audio file :
http://aprovin.linux62.org/others/forums/5.1.wav

I audio card is "maudio revolution 7.1"

I don't have this problem on Windows (5.1 is selected by default).
Anybody can help me ?

Regards

[Rémi Denis-Courmont]

Evidently, VLC and the ALSA device disagree on the channel mapping. I am not sure what the official ALSA order is.

[Nille]

I once had an problem similar to this with ffmpeg and it was because i had my 8 channel card set up as an 6 channel card in alsa.
The manufacture recommends using OSS http://www.m-audio.com/index.php?do=sup ... vers&f=423 but alsa should work.