diff --git a/CHANGES b/CHANGES
index 5c29d3390..03ce886ce 100644
--- a/CHANGES
+++ b/CHANGES
@@ -74,6 +74,7 @@ Bugfixes:
  - Qt: Ensure CLI backend is attached when submitting commands (fixes mgba.io/i/662)
  - Qt: Disable "New multiplayer window" when MAX_GBAS is reached (fixes mgba.io/i/107)
  - Qt: Fix game unpausing after frame advancing and refocusing
+ - Qt: Fix screen background improperly stretching
  - SDL: Fix game crash check
  - SDL: Fix race condition with audio thread when starting
  - SDL: Fix showing version number
diff --git a/src/platform/qt/Window.cpp b/src/platform/qt/Window.cpp
index 4c480a487..046983b81 100644
--- a/src/platform/qt/Window.cpp
+++ b/src/platform/qt/Window.cpp
@@ -132,8 +132,9 @@ Window::Window(ConfigController* config, int playerId, QWidget* parent)
 	resizeFrame(QSize(GB_VIDEO_HORIZONTAL_PIXELS * i, GB_VIDEO_VERTICAL_PIXELS * i));
 #endif
 	m_screenWidget->setPixmap(m_logo);
-	m_screenWidget->setLockAspectRatio(m_logo.width(), m_logo.height());
+	m_screenWidget->setDimensions(m_logo.width(), m_logo.height());
 	m_screenWidget->setLockIntegerScaling(false);
+	m_screenWidget->setLockAspectRatio(true);
 	setCentralWidget(m_screenWidget);
 
 	connect(m_controller, &GameController::gameStarted, this, &Window::gameStarted);
@@ -151,7 +152,6 @@ Window::Window(ConfigController* config, int playerId, QWidget* parent)
 		QPixmap pixmap;
 		pixmap.convertFromImage(currentImage);
 		m_screenWidget->setPixmap(pixmap);
-		m_screenWidget->setLockAspectRatio(width, height);
 	});
 	connect(m_controller, &GameController::gamePaused, m_display, &Display::pauseDrawing);
 #ifndef Q_OS_MAC
@@ -740,7 +740,9 @@ void Window::gameStarted(mCoreThread* context, const QString& fname) {
 	context->core->desiredVideoDimensions(context->core, &width, &height);
 	m_display->setMinimumSize(width, height);
 	m_screenWidget->setMinimumSize(m_display->minimumSize());
+	m_screenWidget->setDimensions(width, height);
 	m_config->updateOption("lockIntegerScaling");
+	m_config->updateOption("lockAspectRatio");
 	if (m_savedScale > 0) {
 		resizeFrame(QSize(width, height) * m_savedScale);
 	}
@@ -802,8 +804,9 @@ void Window::gameStopped() {
 	setWindowFilePath(QString());
 	updateTitle();
 	detachWidget(m_display);
-	m_screenWidget->setLockAspectRatio(m_logo.width(), m_logo.height());
+	m_screenWidget->setDimensions(m_logo.width(), m_logo.height());
 	m_screenWidget->setLockIntegerScaling(false);
+	m_screenWidget->setLockAspectRatio(true);
 	m_screenWidget->setPixmap(m_logo);
 	m_screenWidget->unsetCursor();
 #ifdef M_CORE_GB
@@ -1272,6 +1275,9 @@ void Window::setupMenu(QMenuBar* menubar) {
 	lockAspectRatio->addBoolean(tr("Lock aspect ratio"), avMenu);
 	lockAspectRatio->connect([this](const QVariant& value) {
 		m_display->lockAspectRatio(value.toBool());
+		if (m_controller->isLoaded()) {
+			m_screenWidget->setLockAspectRatio(value.toBool());
+		}
 	}, this);
 	m_config->updateOption("lockAspectRatio");
 
@@ -1662,7 +1668,7 @@ QSize WindowBackground::sizeHint() const {
 	return m_sizeHint;
 }
 
-void WindowBackground::setLockAspectRatio(int width, int height) {
+void WindowBackground::setDimensions(int width, int height) {
 	m_aspectWidth = width;
 	m_aspectHeight = height;
 }
@@ -1671,6 +1677,10 @@ void WindowBackground::setLockIntegerScaling(bool lock) {
 	m_lockIntegerScaling = lock;
 }
 
+void WindowBackground::setLockAspectRatio(bool lock) {
+	m_lockAspectRatio = lock;
+}
+
 void WindowBackground::paintEvent(QPaintEvent*) {
 	const QPixmap* logo = pixmap();
 	if (!logo) {
@@ -1681,10 +1691,12 @@ void WindowBackground::paintEvent(QPaintEvent*) {
 	painter.fillRect(QRect(QPoint(), size()), Qt::black);
 	QSize s = size();
 	QSize ds = s;
-	if (ds.width() * m_aspectHeight > ds.height() * m_aspectWidth) {
-		ds.setWidth(ds.height() * m_aspectWidth / m_aspectHeight);
-	} else if (ds.width() * m_aspectHeight < ds.height() * m_aspectWidth) {
-		ds.setHeight(ds.width() * m_aspectHeight / m_aspectWidth);
+	if (m_lockAspectRatio) {
+		if (ds.width() * m_aspectHeight > ds.height() * m_aspectWidth) {
+			ds.setWidth(ds.height() * m_aspectWidth / m_aspectHeight);
+		} else if (ds.width() * m_aspectHeight < ds.height() * m_aspectWidth) {
+			ds.setHeight(ds.width() * m_aspectHeight / m_aspectWidth);
+		}
 	}
 	if (m_lockIntegerScaling) {
 		ds.setWidth(ds.width() - ds.width() % m_aspectWidth);
diff --git a/src/platform/qt/Window.h b/src/platform/qt/Window.h
index 7b1fec72a..c009c7ffa 100644
--- a/src/platform/qt/Window.h
+++ b/src/platform/qt/Window.h
@@ -214,8 +214,9 @@ public:
 
 	void setSizeHint(const QSize& size);
 	virtual QSize sizeHint() const override;
-	void setLockAspectRatio(int width, int height);
+	void setDimensions(int width, int height);
 	void setLockIntegerScaling(bool lock);
+	void setLockAspectRatio(bool lock);
 
 protected:
 	virtual void paintEvent(QPaintEvent*) override;
@@ -224,6 +225,7 @@ private:
 	QSize m_sizeHint;
 	int m_aspectWidth;
 	int m_aspectHeight;
+	bool m_lockAspectRatio;
 	bool m_lockIntegerScaling;
 };