Yes, i disabled smart conect, i have 2 wireless network, one with 2.4 ghz and another with 5 ghz. The problem is when i leave the room where is placed the router,the signal is very bad and i have only 80 square feet. The devices are disconnected continuously from 5ghz, it jumping on 2.4 ghz but same problem, very very poor signal, and all devices that i'm use are loosing the conectivity with the router. (Model Name: DIR-879 Hardware Version: A1 Firmware Version: 1.07)
I seen on another dlink router, that i can change the Channel Width from 30-140 on 5hz, and on 2.4ghz the channel from 1-14, curently my router is on auto, but on manual i can only select 4 channels. I gues, probably, the firmware is diferent, it has the same interface, i didnt remember the serial number of that router, it was black with 4 antena.
I read about the wireless channel, that it might be interfence in my home, i scaned with an andoid aplication named "wifi analyzer" and the app it recommend to change the wifi chanel between 130-140 for 5ghz and channel 12,13 or 14 for 2.4 ghz.
What do you think guyys? my firmware is for europe, WITH WHICH FIRMWARE CAN CHANGE THE CHANNELS