Fehler: phonon backend plugin could not be loaded

[pospiech]

Der Code der mitdenselben Dlls auf meinem Arbeitsrechner funktioniert (dll im Verzeichnis der .exe) gibt bei mir zuhause den folgenden Fehler:

WARNING: bool __thiscall Phonon::FactoryPrivate::createBackend(void) phonon back
end plugin could not be loaded
WARNING: bool __thiscall Phonon::FactoryPrivate::createBackend(void) phonon back
end plugin could not be loaded
WARNING: bool __thiscall Phonon::FactoryPrivate::createBackend(void) phonon back
end plugin could not be loaded
WARNING: bool __thiscall Phonon::FactoryPrivate::createBackend(void) phonon back
end plugin could not be loaded
Phonon::createPath: Cannot connect Phonon::MediaObject(no objectName) to Phonon:
:AudioOutput(no objectName).
WARNING: bool __thiscall Phonon::FactoryPrivate::createBackend(void) phonon back
end plugin could not be loaded
Phonon::createPath: Cannot connect Phonon::MediaObject(no objectName) to Phonon:
:VideoWidget(no objectName).
Object::connect: No such signal Phonon::VideoPlayer::aboutToFinish()
WARNING: bool __thiscall Phonon::FactoryPrivate::createBackend(void) phonon back
end plugin could not be loaded
WARNING: bool __thiscall Phonon::FactoryPrivate::createBackend(void) phonon back
end plugin could not be loaded

woran muss ich nun drehen damit es geht?