combine-sink: Very high buffer latency (sometimes)
Submitted by Kristian Klausen
Assigned to pul..@..op.org
Description
Created attachment 128418 custom /usr/share/pulseaudio/alsa-mixer/profile-sets/default.conf
Hello
We sell digital signage boxes, and therefor have a Linux image which need to work on most hardware without the customer need to configure anything.
To ensure that, we have a custom default.conf profile-set, which ensure that: hdmi-stereo hdmi-stereo-extra1 hdmi-stereo-extra2 is split out as 3 different sinks, and we then use module-combine-sink to send audio to all the sinks. It work most of the time, but sometimes (often the first time Pulseaudio is started after boot) the sound is "lagging"/sounding totally wrong (not sure how to explain it) and the module is printing errors like:
D: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo] total=63902.33ms sink=367.18ms W: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo] Total latency of output is very high (63902.33ms), most likely the audio timing in one of your drivers is broken. D: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo-extra1] total=359.95ms sink=359.95ms D: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo-extra2] total=63902.00ms sink=366.72ms W: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo-extra2] Total latency of output is very high (63902.00ms), most likely the audio timing in one of your drivers is broken. D: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_1b.0.analog-stereo] total=63902.01ms sink=366.50ms W: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_1b.0.analog-stereo] Total latency of output is very high (63902.01ms), most likely the audio timing in one of your drivers is broken. I: [pulseaudio] module-combine-sink.c: [combined] avg total latency is 48016.57 msec. I: [pulseaudio] module-combine-sink.c: [combined] target latency is 367.18 msec. W: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo] sample rates too different, not adjusting (44100 vs. 324289). I: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo-extra1] new rate of 44069 Hz not within 2‰ of 43877 Hz, forcing smaller adjustment I: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo-extra1] new rate is 43964 Hz; ratio is 0.997; latency is 359.95 msec. W: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_03.0.hdmi-stereo-extra2] sample rates too different, not adjusting (44100 vs. 324288). W: [pulseaudio] module-combine-sink.c: [alsa_output.pci-0000_00_1b.0.analog-stereo] sample rates too different, not adjusting (44100 vs. 324288).
This also cause Firefox (which is the only application running) videos to stutter.
If I open pavucontrol and switch default-sink to any of the other sinks the video start playing normally again as it should and the audio sounds normally.
I have debugged a little, and noticed that "pacmd list-sinks" only show a high (71350.68 ms) "current latency" for the combined sink, and "pactl list sink-inputs" show a very high (94875147 usec) "Buffer Latency" for any of the combine input.
alsa-info: http://www.alsa-project.org/db/?f=d31c9a34dcac7629a572d54c5affd3068074c8e2
Regards Kristian Klausen
Attachment 128418, "custom /usr/share/pulseaudio/alsa-mixer/profile-sets/default.conf":
default.conf