SDL2 audio provider is not working in some Linux distributions.

Versions

• Python: 3.7
• Kivy: 1.11.1
• Kivy installation method: pip
• OS: reported by users in Ubuntu 18.04, Xubuntu 19.04, Debian.

Description

I’ve seen some issue reports (for example, https://github.com/kivy/kivy/issues/6536 and https://github.com/kivy/kivy/issues/6512) that cannot reproduce audio using SDL2. It was also reported with ffpyplayer, but seems to be patched in the latest release (see https://github.com/matham/ffpyplayer/issues/71#issuecomment-554074454).

I’ve been trying different things to make it work, and finally I realised that the problem is the way the wheel is built in pip. If you try to install with pip install https://github.com/kivy/kivy/archive/stable.zip (or with the dev branch) and sdl2 installed, it works because pip builds a fresh wheel. It is not really neccesary to download and compile sdl2 from the web, it is enough to install the sdl2 package from distro repositories.

Code and Logs

Example:

import os

os.environ["KIVY_AUDIO"] = "sdl2"

from kivy.core.audio import SoundLoader

sound = SoundLoader.load('mytest.wav')
if sound:
    print("Sound found at %s" % sound.source)
    print("Sound is %.3f seconds" % sound.length)
    sound.play()

where mytest.wav is any audio file supported by SDL2.

Please, make sure that you see something like:

[INFO   ] [Audio       ] Providers: audio_sdl2

in your log, to ensure that audio_sdl2 is installed and being used.

If you try and have the same issue I’m reporting, you should see something like this:

[CRITICAL] [AudioSDL2   ] Unable to open mixer: b'No such audio device'
[WARNING] Deprecated property "<AliasProperty name=filename>" of object "<kivy.core.audio.audio_sdl2.SoundSDL2>" was accessed, it will be removed in a future version
[WARNING] [AudioSDL2   ] Unable to load (...): b"Audio device hasn't been opened"

If you need help with testing or something, just tell me.

Greetings.

[albertas]

Was getting the same error on Ubuntu 18.04. Reinstalled kivy using your suggested way:

pip install https://github.com/kivy/kivy/archive/stable.zip

And the problem is gone. Thank your @Franccisco.

[pablojimenezmateo]

Was getting the same error on Ubuntu 18.04. Reinstalled kivy using your suggested way:

pip install https://github.com/kivy/kivy/archive/stable.zip

And the problem is gone. Thank your @Franccisco.

I’m having the same issue and this did not fix my problem, I’m still getting the same output. I’m in Ubuntu 18.04.

Following @johnlawrenceaspden instructions the audio works but just for a fraction of a second, the output seems fine:

[INFO   ] [SoundFFPy   ] Using ffpyplayer 4.3.2.dev0
[INFO   ] [Audio       ] Providers: audio_ffpyplayer, audio_sdl2 
xclip version 0.12
Copyright (C) 2001-2008 Kim Saunders et al.
Distributed under the terms of the GNU GPL
[INFO   ] [Clipboard   ] Provider: xclip
[INFO   ] [CutBuffer   ] cut buffer support enabled
[INFO   ] [GL          ] NPOT texture support is available
[WARNING] Deprecated property "<AliasProperty name=filename>" of object "<kivy.core.audio.audio_sdl2.SoundSDL2 object at 0x7fcebf69b2f0>" was accessed, it will be removed in a future version
Sound found at /home/gef/Documents/Hobbes-many/kivy/media/audio/rain.wav
Sound is 300.404 seconds