diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index 6ebe997057..7fa18fea62 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -1491,6 +1491,7 @@ void Application::updateHeartbeat() const {
 
 void Application::aboutToQuit() {
     emit beforeAboutToQuit();
+    DependencyManager::get<AudioClient>()->beforeAboutToQuit();
 
     foreach(auto inputPlugin, PluginManager::getInstance()->getInputPlugins()) {
         if (inputPlugin->isActive()) {
@@ -1592,6 +1593,8 @@ void Application::cleanupBeforeQuit() {
 }
 
 Application::~Application() {
+    DependencyManager::destroy<Preferences>();
+
     _entityClipboard->eraseAllOctreeElements();
     _entityClipboard.reset();
 
diff --git a/libraries/audio-client/src/AudioClient.cpp b/libraries/audio-client/src/AudioClient.cpp
index 5fced85d2d..5208b893ac 100644
--- a/libraries/audio-client/src/AudioClient.cpp
+++ b/libraries/audio-client/src/AudioClient.cpp
@@ -82,10 +82,10 @@ public:
 
     CheckDevicesThread(AudioClient* audioClient)
         : _audioClient(audioClient) {
+    }
 
-        connect(qApp, &QCoreApplication::aboutToQuit, [this] {
-            _quit = true;
-        });
+    void beforeAboutToQuit() {
+        _quit = true;
     }
 
     void run() override {
@@ -159,10 +159,10 @@ AudioClient::AudioClient() :
     _outputDevices = getDeviceNames(QAudio::AudioOutput);
 
     // start a thread to detect any device changes
-    QThread* checkDevicesThread = new CheckDevicesThread(this);
-    checkDevicesThread->setObjectName("CheckDevices Thread");
-    checkDevicesThread->setPriority(QThread::LowPriority);
-    checkDevicesThread->start();
+    _checkDevicesThread = new CheckDevicesThread(this);
+    _checkDevicesThread->setObjectName("CheckDevices Thread");
+    _checkDevicesThread->setPriority(QThread::LowPriority);
+    _checkDevicesThread->start();
 
     configureReverb();
 
@@ -177,6 +177,7 @@ AudioClient::AudioClient() :
 }
 
 AudioClient::~AudioClient() {
+    delete _checkDevicesThread;
     stop();
     if (_codec && _encoder) {
         _codec->releaseEncoder(_encoder);
@@ -184,6 +185,11 @@ AudioClient::~AudioClient() {
     }
 }
 
+void AudioClient::beforeAboutToQuit() {
+    static_cast<CheckDevicesThread*>(_checkDevicesThread)->beforeAboutToQuit();
+}
+
+
 void AudioClient::handleMismatchAudioFormat(SharedNodePointer node, const QString& currentCodec, const QString& recievedCodec) {
     qCDebug(audioclient) << __FUNCTION__ << "sendingNode:" << *node << "currentCodec:" << currentCodec << "recievedCodec:" << recievedCodec;
     selectAudioFormat(recievedCodec);
diff --git a/libraries/audio-client/src/AudioClient.h b/libraries/audio-client/src/AudioClient.h
index 72f5cf5fdc..d6f111cafc 100644
--- a/libraries/audio-client/src/AudioClient.h
+++ b/libraries/audio-client/src/AudioClient.h
@@ -155,6 +155,8 @@ public slots:
     void audioMixerKilled();
     void toggleMute();
 
+    void beforeAboutToQuit();
+
     virtual void setIsStereoInput(bool stereo) override;
 
     void toggleAudioNoiseReduction() { _isNoiseGateEnabled = !_isNoiseGateEnabled; }
@@ -332,6 +334,8 @@ private:
     CodecPluginPointer _codec;
     QString _selectedCodecName;
     Encoder* _encoder { nullptr }; // for outbound mic stream
+
+    QThread* _checkDevicesThread { nullptr };
 };
 
 
diff --git a/libraries/shared/src/RunningMarker.cpp b/libraries/shared/src/RunningMarker.cpp
index 80247150fd..89fb3ada23 100644
--- a/libraries/shared/src/RunningMarker.cpp
+++ b/libraries/shared/src/RunningMarker.cpp
@@ -47,7 +47,7 @@ void RunningMarker::startRunningMarker() {
 
 RunningMarker::~RunningMarker() {
     deleteRunningMarkerFile();
-    _runningMarkerTimer->stop();
+    QMetaObject::invokeMethod(_runningMarkerTimer, "stop", Qt::BlockingQueuedConnection);
     _runningMarkerThread->quit();
     _runningMarkerTimer->deleteLater();
     _runningMarkerThread->deleteLater();