unable to create phonon application on Qt

Hi I am new to QT.I am running Qt 4.7 on Fedora 9.My Application crashes with the the following statements. on execution of
return app.exec();
The inferior stopped because it received a signal from the Operating System.

Signal name : SIGSEGV

Signal meaning :Segmentation fault:wall:

The crash happens on call of the following

Phonon::MediaObject *music =
Phonon::createPlayer(Phonon::MusicCategory,
                      Phonon::MediaSource("/root/Desktop/song/abc.mp3"));
music->play();

I am pasting my main.cpp below. Please help.

#include <QtGui/QApplication>
#include "qmlapplicationviewer.h"
#include <iostream>
#include <fstream>
#include <string>
#include <getopt.h>
#include <id3/misc_support.h>
#include <QtGui/QWidget>
#include <QtGui/QApplication>
#include <QtCore/QTimerEvent>
#include <QtGui/QShowEvent>
#include <QtGui/QIcon>
#include <QtCore/QBasicTimer>
#include <QtGui/QAction>

#include <phonon/audiooutput.h>
#include <phonon/backendcapabilities.h>
#include <phonon/effect.h>
#include <phonon/effectparameter.h>
#include <phonon/effectwidget.h>
#include <phonon/mediaobject.h>
#include <phonon/seekslider.h>
#include <phonon/videowidget.h>
#include <phonon/volumeslider.h>
#include <phonon/mediasource.h>
 #include <Phonon>

#include <sys/types.h>
#include <sys/stat.h>

using namespace std;

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
      app.setApplicationName( "Mu" );

    QmlApplicationViewer viewer;
    viewer.setOrientation(QmlApplicationViewer::ScreenOrientationAuto);
    viewer.setMainQmlFile(QLatin1String("qml/mp02/main.qml"));
    viewer.showExpanded();

    Phonon::MediaObject *music =
Phonon::createPlayer(Phonon::MusicCategory,
                      Phonon::MediaSource("/root/Desktop/song/abc.mp3"));
music->play();


    return app.exec();
}

You should always check NULL pointers, ie
Phonon::MediaObject *music

Hi ,I had alter the program

Phonon::MediaObject *music =new Phonon::MediaObject;
music= NULL;
music =
Phonon::createPlayer(Phonon::MusicCategory, Phonon::MediaSource("/root/Desktop/song/abc.mp3"));

if\( music!= NULL\)
music-&gt;play\(\);

the problem persists even after the change.

I have a similar even when i run the qmediaplayer demo on my system.