In debugging emu10k1 with pulseaudio by printing elem->id->name
SNDERR("Cannot lock ctl elem %s", elem->id->name);
I discovered that sometime "EMU10K1 PCM Send Volume" is locked Is this a bug in alsa-lib or pulseaudio ?
D: alsa-util.c: Checking for superset analog-stereo (front:%f) D: alsa-util.c: Trying front:0 with SND_PCM_NO_AUTO_FORMAT ... D: alsa-util.c: Managed to open front:0 I: alsa-util.c: cannot disable ALSA period wakeups D: alsa-util.c: Maximum hw buffer size is 371 ms I: (alsa-lib)setup.c: Cannot lock ctl elem EMU10K1 PCM Send Volume I: (alsa-lib)setup.c: Cannot lock ctl elem EMU10K1 PCM Send Volume I: (alsa-lib)setup.c: Cannot lock ctl elem EMU10K1 PCM Send Volume I: (alsa-lib)setup.c: Cannot lock ctl elem EMU10K1 PCM Send Volume D: alsa-util.c: Set neither period nor buffer size. I: (alsa-lib)setup.c: Cannot lock ctl elem EMU10K1 PCM Send Volume I: alsa-util.c: snd_pcm_hw_params failed: Device or resource busy