Choppy Audio on Ubuntu 18.04 WSL

[jarussell]

Subject of the issue

Audio playback is choppy on the Windows Subsystem for Linux. It takes 3-4 seconds (variable) to play 1 second of music in pianobar. This same behavior is not experienced with cmus, paplay, nor vlc.

Your environment

• Tried 2 different versions of pianobar building from source (2019.02.14-dev) and from the Ubuntu repository (2017.08.30)
• Linux Distribution is Ubuntu 18.04.2 LTS but it is in the Windows Subsystem for Linux which has many differences
• ffmpeg/libav version and the flags it was compiled with (if you compiled yourself) ffmpeg version 3.4.6-0ubuntu0.18.04.1 Copyright (c) 2000-2019 the FFmpeg developers built with gcc 7 (Ubuntu 7.3.0-16ubuntu3) configuration: --prefix=/usr --extra-version=0ubuntu0.18.04.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared libavutil 55. 78.100 / 55. 78.100 libavcodec 57.107.100 / 57.107.100 libavformat 57. 83.100 / 57. 83.100 libavdevice 57. 10.100 / 57. 10.100 libavfilter 6.107.100 / 6.107.100 libavresample 3. 7. 0 / 3. 7. 0 libswscale 4. 8.100 / 4. 8.100 libswresample 2. 9.100 / 2. 9.100 libpostproc 54. 7.100 / 54. 7.100
• Tried both with and without a config file, behavior is the same and should be reproducible without a config file

Steps to reproduce

1. Install pulseaudio server in Windows by extracting https://github.com/kitor/wsl/blob/master/pulse6.zip to any directory
2. Add "default-server = 127.0.0.1" to /etc/pulse/client.conf (within the WSL environment)
3. sudo apt-get install --no-install-recommends libpulse0 pavucontrol pianobar (within the WSL environment)
4. Start the pulseaudio server on windows (with a flag so that it does not timeout ("--exit-idle-time=-1")
5. Run pavucontrol to ensure that the pulseaudio server is running and has a device
6. Play a song with cmus to make sure that pulseaudio is not the problem
7. Run pianobar, login, and select station

Expected behaviour

Music should play with 1 second lapsing as it plays 1 second's worth of music

Actual behaviour

Music plays, but it plays 1/3-1/4 of a second, pauses for a little bit, and plays another fraction of a second. It takes 3-4 seconds to play 1 actual second of music.

The only error that occurs is "shared memfd open() failed: Function not implemented" but it occurs right before music starts playing (the music still plays, just slowly).

[PromyLOPh]

Are you aware there’s a native Windows port of pianobar available at https://github.com/thedmd/pianobar-windows ?

[jarussell]

I was not aware. It seems like it doesn't really solve the use case that I am looking for because in WSL if I start the windows binary in tmux and detach it to get a headless version like I would on linux, it crashes. I suppose I can report it upstream at WSL.