I’m running debian lenny/sid with kernel 2.6.26-1 on my workstation and for a while, my audio hasn’t been working in most applications (I was most annoyed by the lack of sound in flash), though it has been working in amarok. I was getting error messages like this when trying to do audio playback. These particular messages are from Ekiga:
ALSA lib confmisc.c:1286:(snd_func_refer) Unable to find definition 'defaults.namehint.extended' ALSA lib conf.c:3513:(_snd_config_evaluate) function snd_func_refer returned error: No such file or directory ALSA lib conf.c:3985:(snd_config_expand) Evaluate error: No such file or directory ALSA lib pcm.c:2144:(snd_pcm_open_noupdate) Unknown PCM plughw:0 ALSA lib confmisc.c:1286:(snd_func_refer) Unable to find definition 'defaults.namehint.extended' ALSA lib conf.c:3513:(_snd_config_evaluate) function snd_func_refer returned error: No such file or directory ALSA lib conf.c:3985:(snd_config_expand) Evaluate error: No such file or directory ALSA lib pcm.c:2144:(snd_pcm_open_noupdate) Unknown PCM plughw:0 ALSA lib confmisc.c:1286:(snd_func_refer) Unable to find definition 'defaults.namehint.extended' ALSA lib conf.c:3513:(_snd_config_evaluate) function snd_func_refer returned error: No such file or directory ALSA lib conf.c:3985:(snd_config_expand) Evaluate error: No such file or directory ALSA lib pcm.c:2144:(snd_pcm_open_noupdate) Unknown PCM plughw:0
I finally looked into this and was able to fix it with the simple command
 $ sudo asoundconf reset-default-card