libao alsa output driver fails to open device
An example using ogg123 (a libao user) vs mplayer (which does not use libao)
~ $ cat /etc/libao.conf
default_driver=alsa
dev=default
debug
~ $ ogg123 ~/Radiohead_-_Pyramid_Song_\(sample\).ogg
debug: Loaded driver null (built-in)
debug: Loaded driver wav (built-in)
debug: Loaded driver raw (built-in)
debug: Loaded driver au (built-in)
debug: Loading driver plugins from /usr/lib64/ao/plugins-4...
debug: Loaded driver pulse
debug: Loaded driver alsa
debug: Loaded driver oss
debug: Testing drivers to find playback default...
Audio Device: Advanced Linux Sound Architecture (ALSA) output
Playing: /home/cody/Radiohead_-_Pyramid_Song_(sample).ogg
Ogg Vorbis stream: 2 channel, 44100 Hz
ao_alsa debug: Trying to open ALSA device 'default'
ao_alsa debug: snd_pcm_hw_params_set_access() failed.
ao_alsa debug: Unable to open ALSA device 'default'
ao_alsa ERROR: Unable to open ALSA device 'default' for playback => Invalid argument
ERROR: Cannot open device alsa.
~ $ mplayer -ao alsa ~/Radiohead_-_Pyramid_Song_\(sample\).ogg
MPlayer 1.1-4.7.3 (C) 2000-2012 MPlayer Team
MMX2 supported but disabled
Playing /home/cody/Radiohead_-_Pyramid_Song_(sample).ogg.
libavformat version 54.63.104 (external)
libavformat file format detected.
[vorbis @ 0x7fc9a96a07a0]Warning: not compiled with thread support, using thread emulation
[lavf] stream 0: audio (vorbis), -aid 0
Load subtitles in /home/cody/
==========================================================================
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
libavcodec version 54.92.100 (external)
[vorbis @ 0x7fc9a96a07a0]Warning: not compiled with thread support, using thread emulation
AUDIO: 44100 Hz, 2 ch, floatle, 64.0 kbit/2.27% (ratio: 8000->352800)
Selected audio codec: [ffvorbis] afm: ffmpeg (FFmpeg Vorbis)
==========================================================================
AO: [alsa] 44100Hz 2ch floatle (4 bytes per sample)
Video: no video
Starting playback...
A: 2.1 (02.0) of 28.6 (28.6) 0.8%
Exiting... (Quit)
The specific version of libao used is gentoo's libao-1.1.0-r1
.