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System crash with QMediaPlayer and gstreamer

  • Hi,

    I am currently writing an application with build in audio player.

    When I setup QMediaPlayer, I get (always) the following error:

    Cannot connect to server socket err = No such file or directory
    Cannot connect to server request channel
    jack server is not running or cannot be started

    There are some google results about that, but I did not find any solution to fix it.
    Please note that I do not use jack.

    So far I can live with that error message, but there is a much worse problem:
    Most of the time, the application works fine and does the expected. But sporadically, the application freezes. That is, the whole system freezes. I can turn the mouse around (with a poor frame rate) but I cannot click on anything or interact with any other program. Even switching to a text terminal with <Ctrl><Alt><F1> does not work.
    So I guess an issue with a driver or kernel module.

    I tried mp3 and vorbis, with debugger or without, debug and release mode. Always the same.
    There is no additional warning, error etc.
    The error also occurs when starting the application from console (an executable that ran just before without any problems).

    Linux t420s 3.16-3-amd64 #1 SMP Debian 3.16.5-1 (2014-10-10) x86_64 GNU/Linux

    Qt 5.1.1, C++11

    qmake .../ -r -spec linux-g++-64 CONFIG+=debug

    The part of code causing the issue:
    QMediaPlayer* _player = 0;
    _player = new QMediaPlayer(this);

    QFile tmpFile&#40;filename&#41;;;;
    _player->setMedia(QUrl::fromLocalFile(filename&#41;&#41;;    // <-- this line causes the freezing


    The last system update/upgrade was today.

    I appreciate any help. Thanks!

    btw, the whole project is publicly hosted on github:

  • Hm, no one?

    Maybe a bug in QMediaPlayer / gstreamer / ... ?
    Can you recommend submitting bug reports without exactly knowing what causes it?

    Can you recommend me an other library to play either vorbis or mp3 (or both)? Preferably with seamless Qt integration :D

  • Hey there,

    Since I did not expect my question to be answered here, I posted the same question on stackoverflow.

    Sorry for multiposting. I guess this thread should be closed?

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