diff --git a/src/mqtt.cpp b/src/mqtt.cpp
index 32286a611..b18a7052b 100644
--- a/src/mqtt.cpp
+++ b/src/mqtt.cpp
@@ -41,6 +41,7 @@ std::vector<Mqtt::MQTTSubFunction> Mqtt::mqtt_subfunctions_;
 
 uint16_t                           Mqtt::mqtt_publish_fails_ = 0;
 bool                               Mqtt::connecting_         = false;
+bool                               Mqtt::initialized_        = false;
 uint8_t                            Mqtt::connectcount_       = 0;
 uint16_t                           Mqtt::mqtt_message_id_    = 0;
 std::list<Mqtt::QueuedMqttMessage> Mqtt::mqtt_messages_;
@@ -268,22 +269,20 @@ void Mqtt::on_message(const char * topic, const char * payload, size_t len) {
             bool        cmd_known = false;
             JsonVariant data      = doc["data"];
 
-            JsonObject json; // empty object
-
             if (data.is<char *>()) {
-                cmd_known = Command::call(mf.device_type_, command, data.as<char *>(), n, json);
+                cmd_known = Command::call(mf.device_type_, command, data.as<char *>(), n);
             } else if (data.is<int>()) {
                 char data_str[10];
-                cmd_known = Command::call(mf.device_type_, command, Helpers::itoa(data_str, (int16_t)data.as<int>()), n, json);
+                cmd_known = Command::call(mf.device_type_, command, Helpers::itoa(data_str, (int16_t)data.as<int>()), n);
             } else if (data.is<float>()) {
                 char data_str[10];
-                cmd_known = Command::call(mf.device_type_, command, Helpers::render_value(data_str, (float)data.as<float>(), 2), n, json);
+                cmd_known = Command::call(mf.device_type_, command, Helpers::render_value(data_str, (float)data.as<float>(), 2), n);
             } else if (data.isNull()) {
-                cmd_known = Command::call(mf.device_type_, command, "", n, json);
+                cmd_known = Command::call(mf.device_type_, command, "", n);
             }
 
             if (!cmd_known) {
-                LOG_ERROR(F("MQTT: no matching cmd (%s), invalid data or command failed"), command);
+                LOG_ERROR(F("No matching cmd (%s), invalid data or command failed"), command);
             }
 
             return;
@@ -358,9 +357,10 @@ void Mqtt::start() {
     });
 
     // if MQTT disabled, quit
-    if (!mqtt_enabled_) {
+    if (!mqtt_enabled_ || initialized_) {
         return;
     }
+    initialized_ = true;
 
     mqttClient_->onConnect([this](bool sessionPresent) { on_connect(); });
 
@@ -475,7 +475,7 @@ void Mqtt::on_connect() {
     // first time to connect
     if (connectcount_ == 1) {
         // send info topic appended with the version information as JSON
-        StaticJsonDocument<90> doc;
+        StaticJsonDocument<EMSESP_MAX_JSON_SIZE_SMALL> doc;
         doc["event"]   = "start";
         doc["version"] = EMSESP_APP_VERSION;
 #ifndef EMSESP_STANDALONE
@@ -821,7 +821,7 @@ void Mqtt::register_mqtt_ha_sensor(const char *                prefix,
         LOG_ERROR(F("Failed to publish topic %s"), topic);
     } else {
 #if defined(EMSESP_STANDALONE)
-        LOG_DEBUG(F("Publishing topic=%s, payload=%s"), topic, payload_text);
+        LOG_DEBUG(F("Publishing topic=%s, payload=%s"), topic, payload_text.c_str());
 #else
         LOG_DEBUG(F("Publishing topic %s"), topic);
 #endif
diff --git a/src/mqtt.h b/src/mqtt.h
index 7d2decdc3..377ba11ee 100644
--- a/src/mqtt.h
+++ b/src/mqtt.h
@@ -219,6 +219,7 @@ class Mqtt {
     uint32_t last_publish_sensor_     = 0;
 
     static bool     connecting_;
+    static bool     initialized_;
     static uint16_t mqtt_publish_fails_;
     static uint8_t  connectcount_;