diff --git a/ecal/core/src/readwrite/ecal_reader.cpp b/ecal/core/src/readwrite/ecal_reader.cpp
index 3cede5f81..59c1d62db 100644
--- a/ecal/core/src/readwrite/ecal_reader.cpp
+++ b/ecal/core/src/readwrite/ecal_reader.cpp
@@ -705,7 +705,7 @@ namespace eCAL
         {
           const std::lock_guard<std::mutex> lock(m_event_callback_map_sync);
           auto citer = m_event_callback_map.find(sub_event_dropped);
-          if (citer != m_event_callback_map.end())
+          if (citer != m_event_callback_map.end() && citer->second)
           {
             SSubEventCallbackData data;
             data.type  = sub_event_dropped;