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ALSA backend

This test case tests that ALSA works as a sound backend and that various frontends can be used to communicate with it.

Setup

  1. This test case should be performed on bare-metal machines. To be able to test with virtual machines, consider a USB device pass-through. Leave a note in the comments if you have performed this test using the VM with the USB Passthrough strategy.
  2. The computer must be equipped with a sound device.
  3. Install a desktop version of Fedora 34 (or later).
  4. Make sure the alsa-utils package is installed.
  5. Connect your speakers (headphones) to your computer’s sound device.
  6. Use an audio file in wav format. If you do not have one you can download a suitable audio file. Some default files can be also found in the /usr/share/sounds/ directory.
  7. Perform the following steps as a regular user.

How to test

  1. List the sound devices known to ALSA.

    $ aplay -l

    or (for more details)

    $ aplay -L

    Identify the ones that represent the logical (default, pipewire) or a physical device (sysdefault:CARD=USB, sysdefault:CARD=PCH )

  2. Play the audio file (wav) over the default device.

    $ aplay -D sysdefault <audiofile.wav>

  3. Play the audio file (wav) over a selected ALSA device.

    $ aplay -D hw:X <audiofile.wav>

  4. Play the audio file (wav) over the pipewire device.

    $ aplay -D pipewire <audiofile.wav>

  5. Play the audio file (wav) over the physical device.

    $ aplay -D sysdefault:CARD=USB <audiofile.wav>[1]

  6. Repeat the above step for all physical devices.

  7. Run alsamixer and try setting the volume for a physical device use while playing some audio.

Expected results

  1. aplay -L lists physical and logical devices on the system.
  2. Audio can be played over different endpoints using the aplay command.
  3. Volume levels can be adjusted for physical devices using alsamixer[2]

Footnotes

  1. The device identifier might differ on your machine.

  2. This is valid for devices that support software volume adjusting. USB cards often use dedicated hardware knobs to do it and they cannot be controlled programmatically.