Spotifyd crashes in alsa backend on ALSA error

Spotifyd crashes whenever I connect to it from my phone and start playing music.

To reproduce Steps to reproduce the behavior:

Launch spotifyd using RUST_LOG=debug RUST_BACKTRACE=1 ./target/release/spotifyd --no-daemon
Connect with any device (using the Spotify app on Android, but it probably doesn't matter)
Press the play button.
See the crash.

Log

Here is the log output:

Loading config from "/home/ayke/.config/spotifyd/spotifyd.conf"
No proxy specified
Using software volume controller.
Connecting to AP "ap.spotify.com:443"
Authenticated as "***" !
Country: "NL"
Using Alsa sink with format: S16
Loading <I Can't Sleep Anymore> with Spotify URI <spotify:track:3bs4FFbDtdxE4C882rIszp>
<I Can't Sleep Anymore> (214736 ms) loaded
Alsa error PCM open ALSA function 'snd_pcm_open' failed with error 'UnknownErrno: Unknown errno'
Could not start audio: Alsa error: PCM open failed
Alsa error PCM open ALSA function 'snd_pcm_open' failed with error 'UnknownErrno: Unknown errno'
Could not start audio: Alsa error: PCM open failed
The application panicked (crashed).
Message:  called `Option::unwrap()` on a `None` value
Location: /home/ayke/.cargo/registry/src/github.com-1285ae84e5963aae/librespot-playback-0.2.0/src/audio_backend/alsa.rs:160

  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ BACKTRACE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                                ⋮ 10 frames hidden ⋮                              
  11: core::panicking::panic::h1a22c9da332d8153
      at /rustc/90743e7298aca107ddaa0c202a4d3604e29bfeb6/library/core/src/panicking.rs:115
  12: <librespot_playback::audio_backend::alsa::AlsaSink as librespot_playback::audio_backend::SinkAsBytes>::write_bytes::h2d34d191583d345e
      at <unknown source file>:<unknown line>
  13: <librespot_playback::audio_backend::alsa::AlsaSink as librespot_playback::audio_backend::Sink>::write::h939760c231527758
      at <unknown source file>:<unknown line>
  14: <librespot_playback::player::PlayerInternal as core::future::future::Future>::poll::h049818c5a7e06791
      at <unknown source file>:<unknown line>
  15: futures_executor::local_pool::block_on::hd965bf91a7a89bdb
      at <unknown source file>:<unknown line>
  16: std::sys_common::backtrace::__rust_begin_short_backtrace::h6490d750edd07118
      at <unknown source file>:<unknown line>
  17: core::ops::function::FnOnce::call_once{{vtable.shim}}::h686ea76fbed56867
      at <unknown source file>:<unknown line>
  18: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h81794a412fc9f85c
      at /rustc/90743e7298aca107ddaa0c202a4d3604e29bfeb6/library/alloc/src/boxed.rs:1987
  19: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h262fe31b4a749244
      at /rustc/90743e7298aca107ddaa0c202a4d3604e29bfeb6/library/alloc/src/boxed.rs:1987
  20: std::sys::unix::thread::Thread::new::thread_start::hf1c52a992ed5a078
      at /rustc/90743e7298aca107ddaa0c202a4d3604e29bfeb6/library/std/src/sys/unix/thread.rs:108

Most likely the crash is related to Alsa error PCM open ALSA function 'snd_pcm_open' failed with error 'UnknownErrno: Unknown errno' but even then, IMHO it shouldn't crash.

Host (what you are running librespot on):

OS: Linux
Platform: RPi 3B Rev 1.2

Additional context

There is definitely an alsa problem here though, so the fact that it doesn't start to play is not a bug. But I don't think it should crash.

$ aplay /usr/share/sounds/alsa/Front_Center.wav
aplay: main:830: audio open error: Unknown error 524

EDIT: the actual error was that alsa had rearranged sound cards and it was trying to output on the HDMI port (with no connected display or anything).

librespot-org / librespot

Spotifyd crashes in alsa backend on ALSA error #1110