diff --git a/sdrgui/device/devicesourceapi.cpp b/sdrgui/device/devicesourceapi.cpp
index 89f0e503c..5c9601193 100644
--- a/sdrgui/device/devicesourceapi.cpp
+++ b/sdrgui/device/devicesourceapi.cpp
@@ -176,10 +176,6 @@ void DeviceSourceAPI::setSampleSourcePluginInterface(PluginInterface *iface)
 
 void DeviceSourceAPI::setSampleSourcePluginInstanceGUI(PluginInstanceGUI *gui)
 {
-    if (m_sampleSourcePluginInstanceUI && (gui != m_sampleSourcePluginInstanceUI)) {
-        m_sampleSourcePluginInstanceUI->destroy();
-    }
-
     m_sampleSourcePluginInstanceUI = gui;
 }
 
diff --git a/sdrgui/mainwindow.cpp b/sdrgui/mainwindow.cpp
index 4345e1770..710a14ea7 100644
--- a/sdrgui/mainwindow.cpp
+++ b/sdrgui/mainwindow.cpp
@@ -147,6 +147,10 @@ MainWindow::MainWindow(QWidget* parent) :
         exit(0);
 	}
 
+	// delete previous plugin GUI
+	m_deviceUIs.back()->m_deviceSourceAPI->getPluginInterface()->deleteSampleSourcePluginInstanceGUI(
+	        m_deviceUIs.back()->m_deviceSourceAPI->getSampleSourcePluginInstanceGUI());
+
 	DeviceSampleSource *source = m_deviceUIs.back()->m_deviceSourceAPI->getPluginInterface()->createSampleSourcePluginInstanceInput(
 	        m_deviceUIs.back()->m_deviceSourceAPI->getSampleSourceId(), m_deviceUIs.back()->m_deviceSourceAPI);
 	m_deviceUIs.back()->m_deviceSourceAPI->setSampleSource(source);
@@ -233,6 +237,11 @@ void MainWindow::addSourceDevice()
 
     // Create a file source instance by default
     m_pluginManager->selectSampleSourceBySerialOrSequence("sdrangel.samplesource.filesource", "0", 0, m_deviceUIs.back()->m_deviceSourceAPI);
+
+    // delete previous plugin GUI
+    m_deviceUIs.back()->m_deviceSourceAPI->getPluginInterface()->deleteSampleSourcePluginInstanceGUI(
+            m_deviceUIs.back()->m_deviceSourceAPI->getSampleSourcePluginInstanceGUI());
+
     DeviceSampleSource *source = m_deviceUIs.back()->m_deviceSourceAPI->getPluginInterface()->createSampleSourcePluginInstanceInput(
             m_deviceUIs.back()->m_deviceSourceAPI->getSampleSourceId(), m_deviceUIs.back()->m_deviceSourceAPI);
     m_deviceUIs.back()->m_deviceSourceAPI->setSampleSource(source);
diff --git a/sdrgui/plugin/plugininterface.cpp b/sdrgui/plugin/plugininterface.cpp
index 7db1c63ed..458379fd6 100644
--- a/sdrgui/plugin/plugininterface.cpp
+++ b/sdrgui/plugin/plugininterface.cpp
@@ -6,20 +6,20 @@
 
 void PluginInterface::deleteSampleSourcePluginInstanceGUI(PluginInstanceGUI *ui)
 {
-    ui->destroy();
+    if (ui) { ui->destroy(); }
 }
 
 void PluginInterface::deleteSampleSourcePluginInstanceInput(DeviceSampleSource *source)
 {
-    source->destroy();
+    if (source) { source->destroy(); }
 }
 
 void PluginInterface::deleteSampleSinkPluginInstanceGUI(PluginInstanceGUI *ui)
 {
-    ui->destroy();
+    if (ui) { ui->destroy(); }
 }
 
 void PluginInterface::deleteSampleSinkPluginInstanceOutput(DeviceSampleSink *sink)
 {
-    sink->destroy();
+    if (sink) { sink->destroy(); }
 }
diff --git a/sdrgui/plugin/pluginmanager.cpp b/sdrgui/plugin/pluginmanager.cpp
index 4efe26d58..b3ef7ec25 100644
--- a/sdrgui/plugin/pluginmanager.cpp
+++ b/sdrgui/plugin/pluginmanager.cpp
@@ -355,7 +355,6 @@ int PluginManager::selectSampleSourceByIndex(int index, DeviceSourceAPI *deviceA
             << " seq: " << m_sampleSourceDevices[index].m_deviceSequence;
 
     deviceAPI->stopAcquisition();
-    deviceAPI->setSampleSourcePluginInstanceGUI(0); // this effectively destroys the previous GUI if it exists
 
     deviceAPI->setSampleSourceSequence(m_sampleSourceDevices[index].m_deviceSequence);
     deviceAPI->setHardwareId(m_sampleSourceDevices[index].m_hadrwareId);
@@ -427,7 +426,6 @@ int PluginManager::selectSampleSourceBySerialOrSequence(const QString& sourceId,
             << " seq: " << m_sampleSourceDevices[index].m_deviceSequence;
 
     deviceAPI->stopAcquisition();
-    deviceAPI->setSampleSourcePluginInstanceGUI(0); // this effectively destroys the previous GUI if it exists
 
 	//	m_sampleSourcePluginGUI = pluginGUI;
     deviceAPI->setSampleSourceSequence(m_sampleSourceDevices[index].m_deviceSequence);