Panicks on getting default speakers

[GabrielleShull]

A compiled example panics when running let mut speakers = Speakers::default();

To reproduce the bug:

1. Go to the wavy documentation page.
2. Copy the dependencies to the Cargo.toml file
3. Replace the contents of the main.rs file with the example code.
4. Enter RUST_BACKTRACE=1 cargo run in the terminal.
5. See the error in the backtrace:

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', /home/gabbie/.cargo/registry/src/github.com-1ecc6299db9ec823/wavy-0.8.1/src/ffi/linux/speakers.rs:87:18
stack backtrace:
   0: rust_begin_unwind
             at /rustc/fe5b13d681f25ee6474be29d748c65adcd91f69e/library/std/src/panicking.rs:584:5
   1: core::panicking::panic_fmt
             at /rustc/fe5b13d681f25ee6474be29d748c65adcd91f69e/library/core/src/panicking.rs:143:14
   2: core::panicking::panic
             at /rustc/fe5b13d681f25ee6474be29d748c65adcd91f69e/library/core/src/panicking.rs:48:5
   3: core::option::Option<T>::unwrap
             at /rustc/fe5b13d681f25ee6474be29d748c65adcd91f69e/library/core/src/option.rs:755:21
   4: <wavy::ffi::speakers::Speakers as core::default::Default>::default
             at /home/gabbie/.cargo/registry/src/github.com-1ecc6299db9ec823/wavy-0.8.1/src/ffi/linux/speakers.rs:86:13
   5: <wavy::speakers::Speakers as core::default::Default>::default
             at /home/gabbie/.cargo/registry/src/github.com-1ecc6299db9ec823/wavy-0.8.1/src/speakers.rs:66:21
   6: record_n_play::main
             at ./src/main.rs:32:24
   7: core::ops::function::FnOnce::call_once
             at /rustc/fe5b13d681f25ee6474be29d748c65adcd91f69e/library/core/src/ops/function.rs:227:5

My expectation was that audio would be recorded and played back in real time.

Laptop information:

• OS: NixOS 21.11.337975.eabc3821918 (Porcupine) with Linux kernel version 5.15.50
• Model: HP Laptop 14-dk0028wm

I look forward to learning from this.
Thanks!

[AldaronLau]

@GabrielleShull Thanks for opening this issue! It looks like the wavy docs are suggesting an older version of wavy. Does it still happen if you change wavy to 0.9?

[LennyPenny]

yes, on 0.9 I get

thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', /home/xxx/.cargo/registry/src/github.com-1ecc6299db9ec823/wavy-0.9.1/src/ffi/linux/microphone.rs:79:18
stack backtrace:
   0: rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::panic
   3: core::option::Option<T>::unwrap
             at /build/rustc-1.67.1-src/library/core/src/option.rs:778:21

(also nixos 22.11)

[AldaronLau]

@GabrielleShull @LennyPenny can one of you (or both) run:

arecord --dump-hw-params default

And provide the command's output? I think that might give us more context into why this is happening.

[LennyPenny]

~> arecord --dump-hw-params default
Warning: Some sources (like microphones) may produce inaudible results
         with 8-bit sampling. Use '-f' argument to increase resolution
         e.g. '-f S16_LE'.
Recording WAVE 'default' : Unsigned 8 bit, Rate 8000 Hz, Mono
HW Params of device "ALSA Capture":
--------------------
ACCESS:  MMAP_INTERLEAVED MMAP_NONINTERLEAVED RW_INTERLEAVED RW_NONINTERLEAVED
FORMAT:  U8 S16_LE S24_LE S32_LE FLOAT_LE S24_3LE S24_3BE
SUBFORMAT:  STD
SAMPLE_BITS: [8 32]
FRAME_BITS: [8 2048]
CHANNELS: [1 64]
RATE: [1 384000]
PERIOD_TIME: (0 4294967295)
PERIOD_SIZE: (0 2097152]
PERIOD_BYTES: [128 2097152]
PERIODS: [2 1024]
BUFFER_TIME: (2 4294967295]
BUFFER_SIZE: [1 4194304]
BUFFER_BYTES: [256 4194304]
TICK_TIME: ALL
--------------------

(I aborted it after 10s as it didnt print anything new)