@Kevin_Z Any update on this problem? I really² need help

@Kevin_Z I am sorry, but after checking, the latest firmware for Unifi user now same like mine right now. It's mean that my firmware for my router installed is the latest one right now. Thank you.

@Kevin_Z Yes other device got stable connection, only with Chromecast Ultra I faced this problem. But the old router i didn't have any problem with Chromecast. About channel and width, yes I tried...

My Chromecast Ultra keep disconnecting with wifi after I use new TP-Link C1200. This is never happen with my old router. I tried many suggested solution on Google but still no luck. When I factory...