title: QAudioDeviceInfo finds no default audio device on Ubuntu
body: <p>I am trying to run the basic example from the <a href="http://qt-project.org/doc/qt-5.0/qtmultimedia/qaudiodeviceinfo.html" rel="noreferrer">QAudioDeviceInfo class reference</a>, but Qt is not finding a default audio device.</p>
  
  <p>Running this code shows no output:</p>
  
  <pre><code>foreach (const QAudioDeviceInfo &amp;deviceInfo,  QAudioDeviceInfo::availableDevices(QAudio::AudioOutput))
      qDebug() &lt;&lt; "Device name: " &lt;&lt; deviceInfo.deviceName();
  </code></pre>
  
  <p>I'm running Qt Creator 2.7.1 with Qt 5.0.2 on Ubuntu 13.10. Qt Multimedia was installed via <code>apt-get</code>. My pro file has <code>QT += multimedia</code>. My header file includes:</p>
  
  <pre><code>#include &lt;QAudio&gt;
  #include &lt;QAudioOutput&gt;
  #include &lt;QAudioDeviceInfo&gt;
  </code></pre>
  
  <p>Any ideas as to what I might be doing wrong?</p>