can't output sound on dvb

Hello,

I can't read sound through my dvb card :

mplayer -v -ao mpegpes foo.mp3

-------------[cut here]-------------
Audio file detected.
==========================================================================
Opening audio decoder: [mp3lib] MPEG layer-2, layer-3
dec_audio: Allocating 4608 + 65536 = 70144 bytes for output buffer.
mp3lib: made decode tables with MMX optimization
mp3lib: using MMX optimized decore!
MP3lib: init layer2&3 finished, tables done
MPEG 1.0, Layer III, 44100 Hz 192 kbit Joint-Stereo, BPF: 627
Channels: 2, copyright: No, original: No, CRC: Yes, emphasis: 0
AUDIO: 44100 Hz, 2 ch, 16 bit (0x10), ratio: 24000->176400 (192.0 kbit)
Selected audio codec: [mp3] afm:mp3lib (mp3lib MPEG layer-2, layer-3)
==========================================================================
Checking audio filter chain for 44100Hz/2ch/16bit -> 44100Hz/2ch/16bit...
[libaf] Adding filter dummy
[dummy] Was reinitialized, rate=44100Hz, nch = 2, format = 0x00000001 
and bps = 2
AF_pre: af format: 2 bps, 2 ch, 44100 hz, little endian signed int
AF_pre: 44100Hz 2ch Signed 16-bit (Little-Endian)
Could not open/initialize audio device -> no sound.
Uninit audio filters...
[libaf] Removing filter dummy
uninit audio: mp3lib
Audio: no sound
Freeing 0 unused audio chunks
Video: no video
Freeing 0 unused video chunks

DEMUXER: freeing demuxer at 0x859c360
DEMUXER: freeing sh_audio at 0x8599fc8

Exiting... (End of file)
-------------[cut here]-------------


mplayer -v -ao mpegpes -cache 32 -playlist europe_2-20k.asx

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==========================================================================
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
dec_audio: Allocating 131072 + 65536 = 196608 bytes for output buffer.
FFmpeg's libavcodec audio codec
INFO: libavcodec init OK!
AUDIO: 32000 Hz, 1 ch, 16 bit (0x10), ratio: 2500->64000 (20.0 kbit)
Selected audio codec: [ffwmav2] afm:ffmpeg (DivX audio v2 (ffmpeg))
==========================================================================
Checking audio filter chain for 32000Hz/1ch/16bit -> 32000Hz/2ch/16bit...
[libaf] Adding filter dummy
[dummy] Was reinitialized, rate=32000Hz, nch = 1, format = 0x00000001 
and bps = 2
AF_pre: af format: 2 bps, 1 ch, 32000 hz, little endian signed int
AF_pre: 32000Hz 1ch Signed 16-bit (Little-Endian)
Could not open/initialize audio device -> no sound.
Uninit audio filters...
[libaf] Removing filter dummy
uninit audio: ffmpeg
Audio: no sound
Freeing 0 unused audio chunks
Video: no video
Freeing 0 unused video chunks

DEMUXER: freeing demuxer at 0x859f4c0
DEMUXER: freeing sh_audio at 0x859f140

Exiting... (End of file)
-------------[cut here]-------------




Mplayer plays this right when I specify "-vo mpegpes" instead of "-ao 
mpegpes", but I don't have sound on the DVB output.

mplayer -v -vo mpegpes foo.mp3
mplayer -v -vo mpegpes -cache 32 -playlist europe_2-20k.asx

-------------[cut here]-------------
==========================================================================
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
dec_audio: Allocating 131072 + 65536 = 196608 bytes for output buffer.
FFmpeg's libavcodec audio codec
INFO: libavcodec init OK!
AUDIO: 32000 Hz, 1 ch, 16 bit (0x10), ratio: 2500->64000 (20.0 kbit)
Selected audio codec: [ffwmav2] afm:ffmpeg (DivX audio v2 (ffmpeg))
==========================================================================
Checking audio filter chain for 32000Hz/1ch/16bit -> 32000Hz/2ch/16bit...
[libaf] Adding filter dummy
[dummy] Was reinitialized, rate=32000Hz, nch = 1, format = 0x00000001 
and bps = 2
AF_pre: af format: 2 bps, 1 ch, 32000 hz, little endian signed int
AF_pre: 32000Hz 1ch Signed 16-bit (Little-Endian)
ao2: 32000 Hz  2 chans  Signed 16-bit (Little-Endian)
audio_setup: using '/dev/dsp' dsp device
audio_setup: using '/dev/mixer' mixer device
audio_setup: using 'pcm' mixer device
audio_setup: Can't open audio device /dev/dsp: No such device
AO: [null] 32000Hz 2ch Signed 16-bit (Little-Endian) (2 bps)
AO: Description: Null audio output
AO: Author: Tobias Diedrich
Building audio filter chain for 32000Hz/1ch/16bit -> 32000Hz/2ch/16bit...
[dummy] Was reinitialized, rate=32000Hz, nch = 1, format = 0x00000001 
and bps = 2
[libaf] Adding filter channels
[channels] Changing number of channels to 2
[dummy] Was reinitialized, rate=32000Hz, nch = 1, format = 0x00000001 
and bps = 2
Video: no video
Freeing 0 unused video chunks
Starting playback...
[libaf] Reallocating memory in module channels, old len = 0, new len = 65534
A:         4.2 22.9% 6%
-------------[cut here]-------------

Apparently, it uses sound card output ? I have nothing out of the sound 
card... anyway, i don't use it, so I don't even know if it's setup 
corretly. It doesn't say anything about dvb.

How can I get an audio file get through the dvb card ? Is there 
something wrong with my dvb card ?

I have no problem reading mpegs with video+audio. And I get the same 
result if I read an mpeg when I put "-vo mpegpes" or both "-vo mpegpes 
-ao megpes"

PS : I have 3 dvb Nexus cards. I can't figure out how to tell mplayer to 
read on the other dvb cards.

Regards,
-- 
Alexandre CONRAD - TLV
Research & Development
tel : +33 1 30 80 55 05
fax : +33 1 30 56 55 06
6, rue de la plaine
78860 - SAINT NOM LA BRETECHE
FRANCE