diff --git a/plugins/VOIP/gui/AudioInputConfig.cpp b/plugins/VOIP/gui/AudioInputConfig.cpp
index 6ef39bce5..ea0f2e129 100644
--- a/plugins/VOIP/gui/AudioInputConfig.cpp
+++ b/plugins/VOIP/gui/AudioInputConfig.cpp
@@ -157,6 +157,8 @@ void AudioInputConfig::togglePreview(bool b)
 
 AudioInputConfig::~AudioInputConfig()
 {
+    disconnect( qtTick, SIGNAL( timeout ( ) ), this, SLOT( on_Tick_timeout() ) );
+    
         graph_source->stop() ;
         graph_source->setVideoInput(NULL) ;
         
@@ -350,8 +352,10 @@ void AudioInputConfig::on_qcbTransmit_currentIndexChanged(int v) {
 }
 
 
-void AudioInputConfig::on_Tick_timeout() {
-        if (!inputAudioProcessor) {
+void AudioInputConfig::on_Tick_timeout() 
+{
+        if (!inputAudioProcessor) 
+        {
             inputAudioProcessor = new QtSpeex::SpeexInputProcessor();
             inputAudioProcessor->open(QIODevice::WriteOnly | QIODevice::Unbuffered);
 
@@ -376,7 +380,7 @@ void AudioInputConfig::on_Tick_timeout() {
         // also transmit encoded video
     RsVOIPDataChunk chunk ;
     
-    while(videoInput->getNextEncodedPacket(chunk))
+    while((!videoInput->stopped()) && videoInput->getNextEncodedPacket(chunk))
     {
         videoProcessor->receiveEncodedData(chunk) ;
         chunk.clear() ;
diff --git a/plugins/VOIP/gui/QVideoDevice.cpp b/plugins/VOIP/gui/QVideoDevice.cpp
index 3a0cc4aa9..b81b7b79c 100644
--- a/plugins/VOIP/gui/QVideoDevice.cpp
+++ b/plugins/VOIP/gui/QVideoDevice.cpp
@@ -15,6 +15,11 @@ QVideoInputDevice::QVideoInputDevice(QWidget *parent)
 	_echo_output_device = NULL ;
 }
 
+bool QVideoInputDevice::stopped()
+{
+    return _timer == NULL ;
+}
+
 void QVideoInputDevice::stop()
 {
 	if(_timer != NULL)
@@ -54,6 +59,9 @@ void QVideoInputDevice::start()
 
 void QVideoInputDevice::grabFrame()
 {
+    if(!_timer)
+        return ;
+    
     IplImage *img=cvQueryFrame(_capture_device);    
 
     if(img == NULL)
@@ -87,6 +95,9 @@ void QVideoInputDevice::grabFrame()
 
 bool QVideoInputDevice::getNextEncodedPacket(RsVOIPDataChunk& chunk)
 {
+    if(!_timer)
+        return false ;
+    
     if(_video_processor)
 	    return _video_processor->nextEncodedPacket(chunk) ;
     else 
@@ -100,7 +111,8 @@ uint32_t QVideoInputDevice::currentBandwidth() const
 
 QVideoInputDevice::~QVideoInputDevice()
 {
-	stop() ;
+    stop() ;
+    _video_processor = NULL ;
 }
 
 
diff --git a/plugins/VOIP/gui/QVideoDevice.h b/plugins/VOIP/gui/QVideoDevice.h
index 20a837446..cc92302a2 100644
--- a/plugins/VOIP/gui/QVideoDevice.h
+++ b/plugins/VOIP/gui/QVideoDevice.h
@@ -51,8 +51,8 @@ class QVideoInputDevice: public QObject
         
 		void start() ;
 		void stop() ;
-
-	protected slots:
+		bool stopped();
+protected slots:
 		void grabFrame() ;
 
 	signals: