Hey all, so here's the setup I've got atm: BT homehub 5 connected to 2 powerline adapters. The first adapter connects to it's counterpart one floor up, where it services the tv. The second goes up two floors and connects to my PC. The issue I've been having is when my parents stream anything on the BT vision box or just with netflix to the tv, my connection at my PC either cuts out entirely or drops to just apocalyptic levels. Tethering my phone connected to the wifi network works fine, it just seems that when the downstairs adapter is being used then i just can't even with my pc. Also potentially unrelated but who knows, often playing stuff like war thunder or Arma3 I get random spikes to like 3000 ping. I've called BT about it and they say there's nothing wrong with the router and its connection to the internet tubes, so I'm guessing it's just the things in my house not playing nice with each other.
Unplug one of the two adapters plugged in to the HomeHub. Powerline adapters don't work in pairs; they all share a single connection. With two adapters, the HomeHub is getting confused. If your adapters aren't compatible - and that's why you had two in the HomeHub - you'll need to replace one with a unit compatible with the other two