sound after silence ** Attachment added: "image.png" https://bugs.launchpad.net/ubuntu/+source/pipewire/+bug/2100497/+attachment/5861029/+files/image.png
** Description changed: Ubuntu versions - Plucky, Noble, Oracular pipewire versions - 1.0.5 (noble), 1.3.81(plucky) Upstream link to pipewire bug - https://gitlab.freedesktop.org/pipewire/pipewire/-/issues/4464 + https://gitlab.freedesktop.org/pipewire/pipewire/-/issues/4464 https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/4114 - The set of patches needs to be identified and back-ported to each series. - This was very difficult to test in a local KVM VM, so a VM from AWS was used to verify fix. + The set of patches needs to be identified and back-ported to each series. + This was very difficult to test in a local KVM VM, so a VM from AWS was used to verify fix. The problem started because in Noble we've switched from pulseaudio to pipewire. This issue is not reproducible on pulseaudio. Experimental pipewire package https://packages.debian.org/source/experimental/pipewire + To see the problem happening, you need to install audacity and then + launch 1 terminal + 1 pavucontrol + 1 audacity window and then: + + - Start recording on audacity (even without playing anything) + - Execute the sample app with "./audio_test test_audio.wav" + - Go to pavucontrol and set: + --- In the playback tab, pick your audio output for 'audio_test' app + --- In the recording tab, pick the "Monitor of" the same audio output device for the audacity app + - Stop the recording in audacity and open a new clean audacity window (ctrl+n) + - Start recording and immediately jump to the terminal and execute the sample app (./audio_test test_audio.wav) + + You will be able to see similar behavior in the audio spectrogram + generated by audacity, when comparing it with the one from the upstream + bug (with the incorrect audio being played from the buffer after the + silence). To make it more visible, you can import the audio file + (test_audio.wav) using File>Import, align and compare them. + + Then, switch from pipewire to pulseaudio and repeat those same steps and + you will see that we can't reproduce the problem anymore. + + ``` - ubuntu@vm:~$ ./audio_test2 test_audio.wav + ubuntu@vm:~$ ./audio_test2 test_audio.wav 2025-01-08 20:09:35.610465 INFO (null) - Init 2025-01-08 20:09:35.627511 INFO (null) - Setup player 2025-01-08 20:09:35.627557 DEBUG (null) - Launching pipeline: appsrc is-live=1 do-timestamp=true format=time caps="audio/x-raw,format=S16LE,layout=interleaved,rate=48000,channels=2" name="player_src" ! audioconvert ! audioresample ! queue max-size-buffers=1 silent=true ! pulsesink buffer-time=10000 latency-time=5000 sync=true name="player_sink" 2025-01-08 20:09:35.632150 INFO (null) - Setup capture: filesrc location=test_audio.wav ! decodebin ! queue !audioconvert name=grabber_convert ! audioresample name=grabber_resample ! audio/x-raw,format=S16LE,layout=interleaved,rate=48000,channels=2 !appsink caps="audio/x-raw" sync=true name=appsink 2025-01-08 20:09:35.633253 DEBUG (null) - Set capture callback 2025-01-08 20:09:35.633292 INFO (null) - Start player 2025-01-08 20:09:35.636397 INFO (null) - Start capture 2025-01-08 20:09:35.636651 DEBUG (null) - Playback pipeline state changed from NULL to READY 2025-01-08 20:09:35.636676 DEBUG (null) - Capture pipeline state changed from NULL to READY 2025-01-08 20:09:35.636714 DEBUG (null) - Playback pipeline state changed from READY to PAUSED 2025-01-08 20:09:35.643645 DEBUG (null) - Capture pipeline state changed from READY to PAUSED 2025-01-08 20:09:35.644073 DEBUG (null) - Received buffer after silence (capture pts=0 msec) 2025-01-08 20:09:35.644111 INFO (null) - Simulate silence 2025-01-08 20:09:35.644131 DEBUG (null) - Capture pipeline state changed from PAUSED to PLAYING 2025-01-08 20:09:35.687073 INFO (null) - Simulate silence end 2025-01-08 20:09:35.687535 DEBUG (null) - Playback pipeline state changed from PAUSED to PLAYING 2025-01-08 20:09:40.721732 INFO (null) - Simulate silence ``` ** Also affects: pipewire (Ubuntu Noble) Importance: Undecided Status: New ** Also affects: pipewire (Ubuntu Oracular) Importance: Undecided Status: New ** Also affects: pipewire (Ubuntu Plucky) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2100497 Title: Duplicated audio sample played after silence To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/pipewire/+bug/2100497/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
