Solved QMediaplayer randomly plays part of the audio in a loop

[Andrey Vasilyev]

Hello!
I ran into an unexpected problem while using QMediplayer. Sometimes, when receiving a signal "play", the player starts to play a part of the audio file in a loop for a while . I have not been able to figure out what exactly affects this.
I also added the logging on the call of the signal to play, and I am sure that this signal comes only once.

I tried moving both QMediplayer instances to separate threads, but that didn't solve the problem.
Build with Qt 5.12.6 MinGW 32bit

#include <QApplication>
#include <QMediaPlayer>
#include <QThread>
#include <QMetaType>

#include "logger.h"
#include "routemanager.h"
#include "mqttclient.h"
#include "windowmanager.h"
#include "routewindow.h"

int main(int argc, char *argv[])
{
    qRegisterMetaType<Enums::MqttCommand>("Enums::MqttCommand");
    qRegisterMetaType<Enums::RouteState>("Enums::RouteState");

    QApplication a(argc, argv);

    Logger          logger;
    RouteManager    routeManager;
    WindowManager   windowManager;
    QMediaPlayer    clickPlayer;
    QMediaPlayer    alarmPlayer;

    MQTTclient      *mqttClient = new MQTTclient;
    QThread         *mqttThread = new QThread;

    clickPlayer.setMedia(QUrl("qrc:/sounds/click.wav"));
    alarmPlayer.setMedia(QUrl("qrc:/sounds/alarm.wav"));

    alarmPlayer.setVolume(0);

    mqttClient->moveToThread(mqttThread);
    QObject::connect(mqttThread, &QThread::started, mqttClient, &MQTTclient::initClient);
    QObject::connect(mqttThread, &QThread::finished, mqttClient, &MQTTclient::deleteLater);
    QObject::connect(mqttThread, &QThread::finished, mqttThread, &QThread::deleteLater);

    QObject::connect(&windowManager, &WindowManager::addToLog,              &logger,       &Logger::addToLog);
    QObject::connect(&windowManager, &WindowManager::checkSound,            &alarmPlayer,  &QMediaPlayer::play);
    QObject::connect(&windowManager, &WindowManager::setVolume,             &alarmPlayer,  &QMediaPlayer::setVolume);
    QObject::connect(&windowManager, &WindowManager::click,                 &clickPlayer,  &QMediaPlayer::play);

    QObject::connect(&routeManager, &RouteManager::playAlarm,           &alarmPlayer,   &QMediaPlayer::play);

    QObject::connect(&a, &QApplication::lastWindowClosed, mqttThread, &QThread::quit);
    QObject::connect(&a, &QApplication::aboutToQuit,      mqttThread, &QThread::quit);

    windowManager.initWindows();
    routeManager.initRoutes();

    mqttThread->start();

    return a.exec();
}

[Andrey Vasilyev]

It seems that the problem is somehow related to the work of the Windows defender. After disabling it, the problem did not appear yet.

[Andrey Vasilyev]

The problem was in the Windows firewall. I still don't understand why this was affecting the sound, but disabling the firewall did the trick.