ALSA Error Causes hard crash

[thechubbypanda]

Follows from #1855

Bevy version

Bevy branch: latest 0.5

Operating system & version

Archlinux

What you did

1. No audio playing
2. Create /etc/asound.conf:

defaults.pcm.card 2
defaults.ctl.card 2

as described on the Arch Wiki
3. cargo run

What you expected to happen

Window opens and game runs (using 3d_scene.rs)

What actually happened

thread 'main' panicked at 'build_output_stream failed with all supported formats: BackendSpecific { err: BackendSpecificError { description: "ALSA function 'snd_pcm_sw_params' failed with error 'EINVAL: Invalid argument'" } }', /home/keval/.cargo/registry/src/github.com-1ecc6299db9ec823/rodio-0.13.1/src/stream.rs:208:22
stack backtrace:
   0: rust_begin_unwind
             at /rustc/3d0774d0dc98084d25d95cc1909a8051ebbd9cb1/library/std/src/panicking.rs:517:5
   1: core::panicking::panic_fmt
             at /rustc/3d0774d0dc98084d25d95cc1909a8051ebbd9cb1/library/core/src/panicking.rs:93:14
   2: core::result::unwrap_failed
             at /rustc/3d0774d0dc98084d25d95cc1909a8051ebbd9cb1/library/core/src/result.rs:1617:5
   3: core::result::Result<T,E>::expect
             at /rustc/3d0774d0dc98084d25d95cc1909a8051ebbd9cb1/library/core/src/result.rs:1259:23
   4: <cpal::platform::platform_impl::Device as rodio::stream::CpalDeviceExt>::try_new_output_stream::{{closure}}
             at /home/keval/.cargo/registry/src/github.com-1ecc6299db9ec823/rodio-0.13.1/src/stream.rs:204:17
   5: core::result::Result<T,E>::unwrap_or_else
             at /rustc/3d0774d0dc98084d25d95cc1909a8051ebbd9cb1/library/core/src/result.rs:1083:23
   6: <cpal::platform::platform_impl::Device as rodio::stream::CpalDeviceExt>::try_new_output_stream
             at /home/keval/.cargo/registry/src/github.com-1ecc6299db9ec823/rodio-0.13.1/src/stream.rs:200:12
   7: rodio::stream::OutputStream::try_from_device
             at /home/keval/.cargo/registry/src/github.com-1ecc6299db9ec823/rodio-0.13.1/src/stream.rs:31:32
   8: rodio::stream::OutputStream::try_default
             at /home/keval/.cargo/registry/src/github.com-1ecc6299db9ec823/rodio-0.13.1/src/stream.rs:45:9
   9: <bevy_audio::audio_output::AudioOutput<P> as core::default::Default>::default
             at /home/keval/.cargo/git/checkouts/bevy-9ae29307e9bb7454/db55bf5/crates/bevy_audio/src/audio_output.rs:22:39
  10: <T as bevy_ecs::world::FromWorld>::from_world
             at /home/keval/.cargo/git/checkouts/bevy-9ae29307e9bb7454/db55bf5/crates/bevy_ecs/src/world/mod.rs:928:9
  11: bevy_app::app_builder::AppBuilder::init_non_send_resource
             at /home/keval/.cargo/git/checkouts/bevy-9ae29307e9bb7454/db55bf5/crates/bevy_app/src/app_builder.rs:272:28
  12: <bevy_audio::AudioPlugin as bevy_app::plugin::Plugin>::build
             at /home/keval/.cargo/git/checkouts/bevy-9ae29307e9bb7454/db55bf5/crates/bevy_audio/src/lib.rs:23:9
  13: bevy_app::plugin_group::PluginGroupBuilder::finish
             at /home/keval/.cargo/git/checkouts/bevy-9ae29307e9bb7454/db55bf5/crates/bevy_app/src/plugin_group.rs:104:21
  14: bevy_app::app_builder::AppBuilder::add_plugins
             at /home/keval/.cargo/git/checkouts/bevy-9ae29307e9bb7454/db55bf5/crates/bevy_app/src/app_builder.rs:295:9
  15: expanse::main
             at ./src/main.rs:4:5
  16: core::ops::function::FnOnce::call_once
             at /rustc/3d0774d0dc98084d25d95cc1909a8051ebbd9cb1/library/core/src/ops/function.rs:227:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

Additional information

alsamixer shows correct card as default.

Works fine if using a ~/.asoundrc file:

pcm.!default {
        type hw
        card 2
}

ctl.!default {
        type hw
        card 2
}

When using bevy main I get the following error while playing audio:

ALSA lib pcm_dmix.c:1035:(snd_pcm_dmix_open) unable to open slave

and no error when there's no other audio sources playing.

[Ixentus]

Since this only happens when there are other sources playing, try: https://wiki.archlinux.org/title/Advanced_Linux_Sound_Architecture#Dmix

You might also want to try using pipewire or pulseaudio

[thechubbypanda]

Adding the lines from the wiki:

defaults.pcm.card 2
defaults.ctl.card 2

pcm.dsp {
    type plug
    slave.pcm "dmix"
}

still doesn't help sadly.

How can I force the use of pulseaudio? I have it installed and I believe my plasma session uses it 🤷‍♂️

[thechubbypanda]

In an attempt to get pulseaudio to take presidence over alsa, I installed pulseaudio-alsa which appears to have solved the issue with no alsa config files required. I'm therefore concluding that pulseaudio is now functioning as the primary audio handler and I recommend to anyone else who has this issue to not use alsa smh 🤷‍♂️