Linux:
there is no problem with using it before. After reinstalling the system, it will prompt qt to use phonon to play the wav file, and it will prompt “symbol lookup error: /usr/lib/kde4/plugins/phonon_backend/phonon_gstreamer.so: undefined symbol: _ZNK6Phonon11MediaSource3mrlEv ” this error, and then the program crashes, as if to say the reason for this library version.

My Solution:
find the libphonon_gstreamer.so library in the qt installation directory, then copy it to the directory indicated by the error (rename libphonon_gstreamer.so to phonon_gstreamer.so), replace the phonon_gstreamer.so inside, and return to normal.