diff --git a/MediaImpl.cpp b/MediaImpl.cpp
index a3bbb7c..ecce5fa 100644
--- a/MediaImpl.cpp
+++ b/MediaImpl.cpp
@@ -172,9 +172,10 @@ bool MediaImpl::_eos() const
 //}
 
 
-void MediaImpl::gstNewSampleCallback(GstElement*, int *newBufferCounter)
+GstFlowReturn MediaImpl::gstNewSampleCallback(GstElement*, int *newBufferCounter)
 {
   (*newBufferCounter)++;
+  return GST_FLOW_OK;
 }
 
 MediaImpl::MediaImpl(const QString uri) :
diff --git a/MediaImpl.h b/MediaImpl.h
index 263eb77..6975a72 100644
--- a/MediaImpl.h
+++ b/MediaImpl.h
@@ -105,7 +105,8 @@ public:
 //  };
 
   // GStreamer callback that simply sets the #newSample# flag to point to TRUE.
-  static void gstNewSampleCallback(GstElement *sink, int *newBufferCounter);
+  static GstFlowReturn gstNewSampleCallback(GstElement*, int *newBufferCounter);
+  static GstFlowReturn gstNewPreRollCallback (GstAppSink * appsink, gpointer user_data);
 
 //  static void gstNewAudioBufferCallback(GstElement *sink, GstNewAudioBufferHandlerData *data);