One of the new things are the firewalls in the routers or such. Why this is, is on the web. As a router is your natural firewall (again I'm going to shortchange you here) I turn that off and test again.

Good luck but there are settings to tinker with and I might guess them all but this one seems to come up a lot.

-> Then we have WiFi. Connect with Ethernet as more and more WiFi things clog the air.