title: No Sound Output with QSoundEffect in Qt5.0.2
body: <p>I want to play a wav file if a singal is emitted. For testing i created a pushButton and filled its slot with</p>
  
  <pre><code>QSoundEffect alarm;
  alarm.setSource(QUrl::fromLocalFile("001.wav"));
  alarm.setLoopCount(QSoundEffect::Infinite);
  alarm.setVolume(1.0f);
  alarm.play();
  </code></pre>
  
  <p>But there is no sound if i click on the pushButton. After searching i found people having the same problem with Qt5 but no solution.</p>
  
  <p>Whats the best and simplest solution with Qt5 to just play an uncompressed sound file (wav) and change its volume?</p>
  
  <p>EDIT: I just found out that it works if i add e.g. a QMessageBox (while this message box is open):</p>
  
  <pre><code>QSoundEffect alarm;
  alarm.setSource(QUrl::fromLocalFile("001.wav"));
  alarm.setLoopCount(2);
  alarm.setVolume(0.5f);
  alarm.play();
  
  QMessageBox::information(this, "test", "it works");
  </code></pre>
  
  <p>Has anybody an explanation for this behaviour?</p>