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QAudioProbe not working anymore

  • Hi

    I have a problem with QAudioProbe. It doesn't work under Windows 10. I have 4 kits:

    • Desktop Qt 5.11.1 MinGW 32bit
    • Desktop Qt 5.11.1 MSVC2015 32bit
    • Desktop Qt 5.11.1 MSVC2015 64bit
    • Desktop Qt 5.11.1 MSVC2017 64bit
        m_mediaPlayer = new QMediaPlayer(this);
        m_audioProbe = new QAudioProbe(this);
        connect(m_audioProbe, SIGNAL(audioBufferProbed(QAudioBuffer)), this, SLOT(audioSlot(QAudioBuffer)));
        m_videoWidget = new QVideoWidget;

    This code gives me this error : "qt.multimedia.plugins.directshow: Failed to connect the audio sample grabber", and the signal is never sent.

    QAudioProbe used to work in previous versions of Qt. Is it a bug? How can I fix this problem?

    I apologize for my bad English. It is not my mother tongue.

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    You should start both version of your application with the QT_DEBUG_PLUGINS environment variable set to one to see which plugin is used in both. If it's the same then you may have found a regression.

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