@SlavaGo Thx for sharing your experience. I didn´t mess with my "192.168...." and still the problem appeared though. I´ll install my replacement device soon and hope that I was only unlucky with the...

Ok, thx for reply!

@edichu So is that really the solution recommended by tp-link support? Not to update the device with their latest firmware because it´s not working properly...? I bought an Archer C5400 a couple of...