Remove incorrect gst_message_unref. It should only be called from *sync* handlers that are returning GST_BUS_DROP.

src/core/songloader.cpp

@@ -222,7 +222,6 @@ gboolean SongLoader::BusCallback(GstBus*, GstMessage* msg, gpointer self) {
       break;
   }
 
-  gst_message_unref(msg);
   return GST_BUS_DROP;
 }
 

src/engines/gstenginepipeline.cpp

@@ -195,7 +195,6 @@ gboolean GstEnginePipeline::BusCallback(GstBus*, GstMessage* msg, gpointer self)
       break;
   }
 
-  gst_message_unref(msg);
   return GST_BUS_DROP;
 }