diff --git a/sonoff/support.ino b/sonoff/support.ino
index 020494d7b..7b5b2e472 100644
--- a/sonoff/support.ino
+++ b/sonoff/support.ino
@@ -35,6 +35,10 @@ byte oswatch_blocked_loop = 0;
 //void OsWatchTicker() ICACHE_RAM_ATTR;
 #endif  // USE_WS2812_DMA
 
+#ifdef USE_KNX
+bool KNX_Started = false;
+#endif // USE_KNX
+
 void OsWatchTicker()
 {
   unsigned long t = millis();
@@ -822,13 +826,19 @@ void WifiCheck(uint8_t param)
 #endif  // USE_EMULATION
 #endif  // USE_WEBSERVER
 #ifdef USE_KNX
-      KNXStart();
-#endif // USE_KNX        
+        if (!KNX_Started && Settings.flag.knx_enabled) {
+          KNXStart();
+          KNX_Started = true;
+        }
+#endif // USE_KNX
       } else {
 #if defined(USE_WEBSERVER) && defined(USE_EMULATION)
         UdpDisconnect();
 #endif  // USE_EMULATION
         mdns_begun = false;
+#ifdef USE_KNX
+        KNX_Started = false;
+#endif // USE_KNX
       }
     }
   }