diff --git a/src/platform/arduino/MQTTTelemetry.cpp b/src/platform/arduino/MQTTTelemetry.cpp
index b0acfce..8722143 100644
--- a/src/platform/arduino/MQTTTelemetry.cpp
+++ b/src/platform/arduino/MQTTTelemetry.cpp
@@ -108,6 +108,7 @@ MQTTTelemetry::MQTTTelemetry() : BufferedInputSource("MQTT"),
     m_logPrinter(this)
 {
     m_debugTopic = String("renderbug/") + Platform::deviceID();
+    memset(m_hostBuf, 0, sizeof(m_hostBuf));
 }
 
 void
@@ -201,9 +202,15 @@ MQTTTelemetry::handleEventOnline(const InputEvent& evt)
 void
 MQTTTelemetry::handleConfigChange(const InputEvent& event)
 {
-  const JsonObject& obj = event.as<JsonObject>();
-  strncpy(m_hostBuf, obj["mqtt.ip"].as<JsonString>().c_str(), sizeof(m_hostBuf));
-  m_mqtt.disconnect();
+  Log.notice("Config change in mqtt");
+  const JsonObject* obj = event.as<JsonObject>();
+  if (obj->containsKey("mqtt.ip")) {
+    const char* newIP = (*obj)["mqtt.ip"].as<JsonString>().c_str();
+    Log.notice("ip: %s", newIP);
+    strncpy(m_hostBuf, newIP, sizeof(m_hostBuf));
+    m_hostBuf[sizeof(m_hostBuf)-1] = 0;
+    m_mqtt.disconnect();
+  }
 }
 
 void
@@ -217,6 +224,7 @@ MQTTTelemetry::loop()
 void
 MQTTTelemetry::handleEvent(const InputEvent& evt)
 {
+  BufferedInputSource::handleEvent(evt);
   OnlineTaskMixin::handleEvent(evt);
   ConfigTaskMixin::handleEvent(evt);
 }
@@ -225,7 +233,11 @@ void
 MQTTTelemetry::onOnline()
 {
   m_needHeartbeat = true;
-  m_mqtt.setServer(m_hostBuf, 1883);
+  if (strlen(m_hostBuf) > 0) {
+    m_mqtt.setServer(m_hostBuf, 1883);
+  } else {
+    Log.warning("mqtt.ip is not configured, no connection possible");
+  }
   m_mqtt.setBufferSize(1024);
   m_mqtt.setCallback(&MQTTTelemetry::s_callback);
 }