diff -r 9e67c5f9c994 -r b5ae9017194f thermferm/mqtt.c
--- a/thermferm/mqtt.c	Mon May 08 17:03:25 2017 +0200
+++ b/thermferm/mqtt.c	Mon May 08 20:54:51 2017 +0200
@@ -581,7 +581,8 @@
         return;
     }
 
-    mosquitto_log_callback_set(mosq, my_log_callback);
+    if (debug)
+    	mosquitto_log_callback_set(mosq, my_log_callback);
     mosquitto_max_inflight_messages_set(mosq, max_inflight);
     mosquitto_connect_callback_set(mosq, my_connect_callback);
     mosquitto_disconnect_callback_set(mosq, my_disconnect_callback);