Ubuntu 20.04 / Pulseaudio RTP receive sound lags
just upgraded some of my computers to Ubuntu 20.04, also tried with fresh install, in all case the pulseaudio rtp receive module is giving me very poor sound (lags, buffer underruns).
See attached pa-info.txt.
Steps to reproduce
pacmd load-module module-null-sink sink_name=MyNullSink pacmd load-module module-rtp-send source=MyNullSink.monitor loop=true pacmd load-module module-rtp-recv
And then play something in the null sink, loopback sound will be bad (lags).
What I noticed :
- if I open the rtp stream with vlc, it's ok, sound is good.
- Ubuntu 20 uses PulseAudio 13.99, aka (I guess) PulseAudio 14 which implements RTP through gstreamer, which is new. So I tested my rtp stream with gstreamer:
gst-launch-1.0 udpsrc address=188.8.131.52 port=46586 caps="application/x-rtp, media=audio, payload=10, clock-rate=44100" ! .recv_rtp_sink_0 rtpbin ! rtpL16depay ! audioconvert ! audioresample ! pulsesink
And it works fine, so I guess there is an issue in the new module-rtp-recv.so bundled with PulseAudio and that is now based on gstreamer.
What is the current bug behavior?
Sound lags (buffer underflows).
What is the expected correct behavior?
Sound doesn't lag