Hello, alzhao.

Yes, no problem with router, just Power LED always OFF now, other LEDS OK, never touched LED config.
I have nothing in USB port, just SD card and one wired network in LAN Port1, WAN and WAN6 are disabled in Interfaces, because always using WISP which I connect with luci no with GL.UI. Never disconnects from AP at 50mts.
Plugins: upnp, wifi-schedule, samba and ddns in luci.
Also when updated firmware reset factory, power led OFF too, never ON and no LAN cable no plugins installed yet, factory config only.

Thank you!