Change phonon backend to vlc backend

[stereomatching]

I download "phonon backend":http://people.videolan.org/~jb/phonon/phonon-vlc-4.5-0.4.1-sdk.7z
remove original dll and .a files from ../plugins/phonon_backend and replace them with the
"phonon_vlc.dll". I test it with the examples "music player":http://doc.qt.nokia.com/4.7-snapshot/phonon-qmusicplayer.html
But it do not work as expected

OS : win7 64bits
Qt : 4.8.2
compiler : minGW4.6.2