diff --git a/lib/PubSubClient/src/PubSubClient.h b/lib/PubSubClient/src/PubSubClient.h
index 225fd5a98..e2f1b32b1 100644
--- a/lib/PubSubClient/src/PubSubClient.h
+++ b/lib/PubSubClient/src/PubSubClient.h
@@ -24,7 +24,7 @@
 // MQTT_MAX_PACKET_SIZE : Maximum packet size
 #ifndef MQTT_MAX_PACKET_SIZE
 //#define MQTT_MAX_PACKET_SIZE 128
-#define MQTT_MAX_PACKET_SIZE 400
+#define MQTT_MAX_PACKET_SIZE 512
 #endif
 
 // MQTT_KEEPALIVE : keepAlive interval in Seconds
diff --git a/platformio.ini b/platformio.ini
index e33913f18..c04f7e125 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -17,6 +17,6 @@ framework = arduino
 board = esp01_1m
 ; ESP8285 - Sonoff Touch and Sonoff 4CH
 ; board = esp8285
-build_flags = -Wl,-Tesp8266.flash.1m64.ld -DMQTT_MAX_PACKET_SIZE=400
+build_flags = -Wl,-Tesp8266.flash.1m64.ld -DMQTT_MAX_PACKET_SIZE=512
 
 lib_deps = PubSubClient, NeoPixelBus, IRremoteESP8266, ArduinoJSON