glitches when changing volume
I've been experiencing short glitches, like intervals of 100ms-200ms of silence, every time I change the volume.
This happens with the following setup
#!/bin/sh
# load any stereo USB audio device, tested with built-in soundcard
# and with cheap USB audio dongle
# appending tsched=0 here fails to help
pactl load-module module-alsa-sink sink_name=hw device=hw:0
pactl load-module module-combine-sink slaves=hw sink_name=combined
# no glitches if this is commented (& remap-sink master set to combined)
pactl load-module module-equalizer-sink sink_master=combined sink_name=eq
# no glitches if this is commented (& equalizer renamed to noise)
pactl load-module module-remap-sink sink_name=noise master=eq
(I don't load module-udev-detect
in /etc/pulse/default.pa
because I can't figure out how to use the names it assigns to the automatically detected sinks. (looking at the output of pacmd list sinks
). Also, I noticed that there is no way to point PulseAudio to a different config file, so it is difficult to experiment with different configurations. Maybe it would be good to fix these issues too. Anyway I hope this minimal test case is good enough)
Changing the volume like this:
pactl set-sink-volume noise +1\%
causes a glitch every time.
Note that I am using module-remap-sink
as a way to use a new sink name to reference an existing sink; it's not doing any remapping, it is supposed to just copy input to output. Let me know if there is a more accepted way to create "copy" sinks. It's not exactly an "alias" because I sometimes want to have a separate volume control for the new sink.
The CPU usage of PulseAudio is only 6%, the CPU is a 3.5 GHz Xeon.