Qt: Fix audio volume/mute being lost when restarting emulation

src/duckstation-qt/audiosettingswidget.cpp

@@ -79,5 +79,5 @@ void AudioSettingsWidget::onOutputMutedChanged(int new_state)
 {
   const bool muted = (new_state != 0);
   m_host_interface->SetBoolSettingValue("Audio", "OutputMuted", muted);
-  m_host_interface->setAudioOutputVolume(muted ? 0 : m_ui.volume->value());
+  m_host_interface->setAudioOutputMuted(muted);
 }

src/duckstation-qt/qthostinterface.cpp

@@ -897,6 +897,22 @@ void QtHostInterface::setAudioOutputVolume(int value)
 
   if (m_audio_stream)
     m_audio_stream->SetOutputVolume(value);
+
+  m_settings.audio_output_volume = value;
+}
+
+void QtHostInterface::setAudioOutputMuted(bool muted)
+{
+  if (!isOnWorkerThread())
+  {
+    QMetaObject::invokeMethod(this, "setAudioOutputMuted", Q_ARG(bool, muted));
+    return;
+  }
+
+  if (m_audio_stream)
+    m_audio_stream->SetOutputVolume(muted ? 0 : m_settings.audio_output_volume);
+
+  m_settings.audio_output_muted = muted;
 }
 
 void QtHostInterface::startDumpingAudio()

src/duckstation-qt/qthostinterface.h

@@ -136,6 +136,7 @@ public Q_SLOTS:
   void loadState(bool global, qint32 slot);
   void saveState(bool global, qint32 slot, bool block_until_done = false);
   void setAudioOutputVolume(int value);
+  void setAudioOutputMuted(bool muted);
   void startDumpingAudio();
   void stopDumpingAudio();
   void saveScreenshot();