... problems with Qt 5.4 and that was my problem.
https://bugreports.qt.io/browse/QTBUG-42286
In case you try to run this software and some files don't play, please, try to
install the K-Lite Codec Pack 1100 Basic
http://downloads.ddigest.com/software/download.php?sid=1089&ssid=0&did=374
---------------------------------------------------------------------------