it seems that tp-link didn't enable this on C3200. for the disconnection, it happens on all the devices? wireless or wired? any new device joining before problem happens?

how about reporting this to tp-link email support so they will take this seriously.

thanks for sharing!

to locate the problem, if your connect that Ubuntu laptop directly to the modem bypass the router, can you open that website? if you can not, which means that this is isp or modem issue. if you can,...

how about sending a feedback to tp-link email support so they will consider this?

i think that guest network will separate it from the reset network including your player,xbox,main Wi-Fi on the TL-WPA8760 and router. You can test it by connecting one of your laptop to the guest...