Comment 34 for bug 1315212

http://mailman.alsa-project.org/pipermail/alsa-devel/2008-October/011913.html

: module-alsa-sink.c: Using 4 fragments of size 8816 bytes, buffer time is 99.95ms
D: module-alsa-sink.c: hwbuf_unused_frames=0
D: module-alsa-sink.c: setting avail_min=1
I: module-alsa-sink.c: Volume ranges from 0 to 31.
I: module-alsa-sink.c: Volume ranges from -46.50 dB to 0.00 dB.
I: alsa-util.c: ALSA device lacks separate volumes control for channel 'rear-left'
I: module-alsa-sink.c: Using hardware volume control. Hardware dB scale supported.
D: alsa-util.c: snd_pcm_dump():
D: alsa-util.c: Multi PCM
D: alsa-util.c: Channel bindings:
D: alsa-util.c: 0: slave 0, channel 0
D: alsa-util.c: 1: slave 0, channel 1
D: alsa-util.c: 2: slave 1, channel 0
D: alsa-util.c: 3: slave 1, channel 1
D: alsa-util.c: Its setup is:
D: alsa-util.c: stream : PLAYBACK
D: alsa-util.c: access : RW_INTERLEAVED
D: alsa-util.c: format : S16_LE
D: alsa-util.c: subformat : STD
D: alsa-util.c: channels : 4
D: alsa-util.c: rate : 44100
D: alsa-util.c: exact rate : 44100 (44100/1)
D: alsa-util.c: msbits : 16
D: alsa-util.c: buffer_size : 4408
D: alsa-util.c: period_size : 1102
D: alsa-util.c: period_time : 24988
D: alsa-util.c: tstamp_mode : NONE
D: alsa-util.c: period_step : 1
D: alsa-util.c: avail_min : 1102
D: alsa-util.c: period_event : 0
D: alsa-util.c: start_threshold : -1
D: alsa-util.c: stop_threshold : -1
D: alsa-util.c: silence_threshold: 0
D: alsa-util.c: silence_size : 0
D: alsa-util.c: boundary : 1155530752
D: alsa-util.c: Slave #0: Hooks PCM
D: alsa-util.c: Its setup is:
D: alsa-util.c: stream : PLAYBACK
D: alsa-util.c: access : MMAP_INTERLEAVED
D: alsa-util.c: format : S16_LE
D: alsa-util.c: subformat : STD
D: alsa-util.c: channels : 2
D: alsa-util.c: rate : 44100
D: alsa-util.c: exact rate : 44100 (44100/1)
D: alsa-util.c: msbits : 16
D: alsa-util.c: buffer_size : 4408
D: alsa-util.c: period_size : 1102
D: alsa-util.c: period_time : 24988
D: alsa-util.c: tstamp_mode : NONE
D: alsa-util.c: period_step : 1
D: alsa-util.c: avail_min : 1102
D: alsa-util.c: period_event : 0
D: alsa-util.c: start_thr
D: module-alsa-sink.c: Thread starting up
D: rtpoll.c: Acquired POSIX realtime signal SIGRTMIN+29
D: module-alsa-sink.c: Read hardware volume: 0: 87% 1: 87% 2: 87% 3: 87%
I: module-alsa-sink.c: Starting playback.
I: (alsa-lib)pcm_hw.c: SNDRV_PCM_IOCTL_START failed

the playback stream has been started and pcm state is running but pulseaudio still call snd_pcm_start()