MediaPlayer Segfault with null defaultAudioOutput

Kuzma30

I have custom board with CM4 and MAX98357A for sound.
Sound system - ALSA (without PulseAudio. I have problems with it)
I use dev.xml (Qt 6.7.0) manifest in boot2qt distro.
I have app that consist of many QML files. Its under active development. App works fine without SoundEffect. After start I can see GUI after 5 sec. Switching menu( each menu in separate file and activated by Loader in QML) - less second.

When I add SoundEffect to my app it dramatically slow down. Loading app before GUI shown - 20 sec. Switching menu - near 5 sec.

I use +- 20 SoundEffect, with different sound files source in my code. Is it correct practice or I must use one SoundEffect and change source var on it?

Kuzma30

I also try switch from SoundEffect to MediaPlayer but get SEGFAULTS

MediaPlayer {
        id: lostLinkSound
        source: "qrc:/qml/Component/Sound/lost_link_"+trans.currentLanguage+".wav"
        audioOutput: AudioOutput {}
        }

Log for error

gdb ./Ferti 
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License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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Type "show copying" and "show warranty" for details.
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Type "show configuration" for configuration details.
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For help, type "help".
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Reading symbols from ./Ferti...
(gdb) r
Starting program: /usr/lib/Ferti 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/libthread_db.so.1".
[New Thread 0xb2b202c0 (LWP 29448)]
[New Thread 0xb188b2c0 (LWP 29449)]
[Detaching after vfork from child process 29450]
[Detaching after vfork from child process 29455]
[New Thread 0xb0d822c0 (LWP 29456)]
[New Thread 0xaed3a2c0 (LWP 29457)]

Thread 1 "Ferti" received signal SIGSEGV, Segmentation fault.
0xaef219b0 in gst_device_create_element () from /lib/libgstreamer-1.0.so.0

Kuzma30

More info and tests

root@b2qt-raspberrypi4:/usr/lib# aplay -L
null
    Discard all samples (playback) or generate zero samples (capture)
sysdefault:CARD=MAX98357A
    MAX98357A, bcm2835-i2s-HiFi HiFi-0
    Default Audio Device
root@b2qt-raspberrypi4:/usr/lib# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: MAX98357A [MAX98357A], device 0: bcm2835-i2s-HiFi HiFi-0 [bcm2835-i2s-HiFi HiFi-0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
root@b2qt-raspberrypi4:/usr/lib#

I add in my code.

MediaDevices {
            id: mediaDevices
            Component.onCompleted: {
                console.log("Outputs Audio devices List: " + audioOutputs)
                console.log("Outputs Audio devices (defaults): " + defaultAudioOutput)
            }
}

In log I see

qml: Outputs Audio devices List: QAudioDevice(default, , true, Output),QAudioDevice(sysdefault:CARD=MAX98357A, MAX98357A, bcm2835-i2s-HiFi HiFi-0
Default Audio Device, false, Output)
qml: Outputs Audio devices (defaults): QAudioDevice(default, , true, Output)

And when I add

MediaPlayer {
       id: playMessage
       source: "" 
       audioOutput: AudioOutput {
           id: playerOutput
           device: mediaDevices.defaultAudioOutput

}
}

it SEGFAULTS

SGaist

Hi,

The segmentation fault seem to have occurred in libgstreamer. Can you check that GStreamer is working properly ?

Kuzma30

@SGaist
I hear sound only when manually specify output audio device (without parameters I get no sound, but see how time is changing 0:00:12.0 / 0:01:00.0 )

gst-play-1.0 BabyElephantWalk60.wav --audiosink='alsasink device=hw:0,0'

p.s.
my asound.conf

pcm.speakerbonnet {
   type hw card 0
}

pcm.dmixer {
   type dmix
   ipc_key 1024
   ipc_perm 0666
   slave {
     pcm "speakerbonnet"
     period_time 0
     period_size 1024
     buffer_size 8192
     rate 44100
     channels 2
   }
}

ctl.dmixer {
    type hw card 0
}

pcm.softvol {
    type softvol
    slave.pcm "dmixer"
    control.name "PCM"
    control.card 0
}

ctl.softvol {
    type hw card 0
}

pcm.!default {
    type             plug
    slave.pcm       "softvol"
}

SGaist

Looks like there's an issue on your system. Are you sure it's properly configured ?

Kuzma30

@SGaist
I refactor my code to use only 3 SoundEffect and change source variable in code when I need new sound. It solve my problem now but I still have non working MediaPlayer.

Kuzma30

Now some time I see

ALSA lib /usr/src/debug/alsa-lib/1.2.9-r0/src/pcm/pcm.c:8675:(snd_pcm_recover) underrun occurred

in console

SGaist

Are you sure alsa is properly configured for your hardware ?

Kuzma30

@SGaist
How to check this?

SGaist

@Kuzma30 ask the Raspberry Pi folks.