diff --git a/WifiControlSensor/MQTT.ino b/WifiControlSensor/MQTT.ino
index 531ec8e..a1190e2 100644
--- a/WifiControlSensor/MQTT.ino
+++ b/WifiControlSensor/MQTT.ino
@@ -29,8 +29,6 @@ const int gpioWatched[] = CONFIG_MQTT_CONTROLLED_GPIO;
 #define IP_FEED_FORMAT "/feeds/%s/%s/configuration/ip/addr"
 
 char *mqttId;
-char GPIO_FEED[MAXSUBSCRIPTIONS][FEED_MAX_SIZE] = {};
-char GPIO_SET_FEED[MAXSUBSCRIPTIONS][FEED_MAX_SIZE] = {};
 
 Adafruit_MQTT_Publish * mqttGpio[MAXSUBSCRIPTIONS] = {};
 
@@ -58,14 +56,8 @@ int MqttSetup(char *server, char *user, char *passwd, int port, char * hostname)
   mqtt_ip =  MqttCreatePublisher(IP_FEED_FORMAT, user, mqttId);
 
   for (uint i = 0 ; i < NB_ELEMENTS(gpioWatched) && i < MAXSUBSCRIPTIONS; i++) {
-    snprintf(GPIO_FEED[i], FEED_MAX_SIZE, GPIO_FEED_FORMAT, user, mqttId, gpioWatched[i]);
-    snprintf(GPIO_SET_FEED[i], FEED_MAX_SIZE, GPIO_SET_FEED_FORMAT, user, mqttId, gpioWatched[i]);
-
-    Adafruit_MQTT_Subscribe *gpioSet = new Adafruit_MQTT_Subscribe(mqtt, GPIO_SET_FEED[i]);
-    mqtt->subscribe(gpioSet);
-
-    Adafruit_MQTT_Publish *gpio =  new Adafruit_MQTT_Publish(mqtt, GPIO_FEED[i]);
-    mqttGpio[i] = gpio;
+    mqtt->subscribe(MqttCreateSubscribe(GPIO_SET_FEED_FORMAT, user, mqttId, gpioWatched[i]));
+    mqttGpio[i] = MqttCreatePublisher(GPIO_FEED_FORMAT, user, mqttId, gpioWatched[i]);
   }
   return 0;
 }
@@ -76,12 +68,16 @@ Adafruit_MQTT_Publish *MqttCreatePublisher(const char *fmt, ...){
   va_start (args, fmt);
   vsnprintf(buf, sizeof(buf), (const char *)fmt, args);
   va_end(args);
-  String *url = new String(buf);
-  return new Adafruit_MQTT_Publish(mqtt, url->c_str());
+  return new Adafruit_MQTT_Publish(mqtt, strdup(buf));
 }
 
-bool MqttIsConfigured() {
-  return isMqttConfigured;
+Adafruit_MQTT_Subscribe *MqttCreateSubscribe(const char *fmt, ...){
+  char buf[FEED_MAX_SIZE];
+  va_list args;
+  va_start (args, fmt);
+  vsnprintf(buf, sizeof(buf), (const char *)fmt, args);
+  va_end(args);
+  return new Adafruit_MQTT_Subscribe(mqtt, strdup(buf));
 }
 
 int MqttIsConnected() {