diff --git a/src/ebusd/mainloop.cpp b/src/ebusd/mainloop.cpp
index 6d41e67e..844bea53 100644
--- a/src/ebusd/mainloop.cpp
+++ b/src/ebusd/mainloop.cpp
@@ -359,12 +359,14 @@ void MainLoop::run() {
     time(&now);
     if (!dataSinks.empty()) {
       messages.clear();
+      m_messages->lock();
       m_messages->findAll("", "", "*", false, true, true, true, true, true, sinkSince, now, false, &messages);
       for (const auto message : messages) {
         for (const auto dataSink : dataSinks) {
           dataSink->notifyUpdate(message);
         }
       }
+      m_messages->unlock();
       sinkSince = now;
     }
     if (netMessage == nullptr) {
diff --git a/src/ebusd/mqtthandler.cpp b/src/ebusd/mqtthandler.cpp
index 1ded7a24..78df67af 100644
--- a/src/ebusd/mqtthandler.cpp
+++ b/src/ebusd/mqtthandler.cpp
@@ -747,8 +747,8 @@ void MqttHandler::run() {
       }
     }
     if (!m_updatedMessages.empty()) {
+      m_messages->lock();
       if (m_connected) {
-        m_messages->lock();
         for (auto it = m_updatedMessages.begin(); it != m_updatedMessages.end(); ) {
           const vector<Message*>* messages = m_messages->getByKey(it->first);
           if (messages) {
@@ -764,11 +764,11 @@ void MqttHandler::run() {
           }
           it = m_updatedMessages.erase(it);
         }
-        m_messages->unlock();
         time(&lastUpdates);
       } else {
         m_updatedMessages.clear();
       }
+      m_messages->unlock();
     }
     if ((!m_connected && !Wait(5)) || (needsWait && !Wait(1))) {
       break;