Always empty metadata

Question

I'm writing audio player using QtMutimedia, and need got audio file metadata. I'm using this code, but always returns empty strings on every file. How fix this?

Qt 5.15.2 MinGw

QStringList meta = player->availableMetaData();
qDebug() << "File meta: ";

foreach(QString data, meta){
    qDebug() << data;
}