Dear Friends, I have a problem that it drive me mad! Tested In several ESP8266 Based on ESP-12F modules all the same problem, I running my sketch that is Arduino ESP8266 Core 2.3.0 ( also tested with the git recent version, same problem... ) based mostly used Blynk 0.4.7 library. When I running the module(s) at my home using TpLink 4G router M7350 UN then keeping printing the ESP Free Heap this memory always auto reduced without a reason... WITH Exactly the same hardware/software , when I move the setup to my works WiFi THEN I HAVE NOT any ESP Free Heap memory "Auto" reduction... I can suppose that something is wrong in the TCP/IP stack but I am not software engineer. Please try to help me. The important point is that with all the same except the routers the behaviour changes dramatically from working OK ( when at work WiFi ) to very fast heap auto reduction ( when at home with 4G router ).