Edited by Levitsky86 at 2018-1-29 17:23
Thanks for your help!
I read the forum many times but I have never found that information you mentioned about build-suspend. So, if I have LibreELEC 03/2017 then I should try Key_power.
As for the Wi-Fi I never use it and my board is connected with Ethernet wire but I it looses my MAC address (LAN MAC address, not Wi-Fi)... Maybe it's because I used Suspend and not Power off, I would try Power off then.