My PC sits in the kitchen and I tend to cable in rather than wifi so I cabled in Via the BT wifi Disc, doing speed tests on Ookla, when connected via Disc I am only getting 150mbps, so I bought a 20m ethernet cable to connect direct to smart hub and subsequent speed test showed 300mbps.
Question, is the disc faulty or is it throttled to 150mbps?
I don’t know the BT discs but if it’s acting as an extender without a backhaul connection and it’s just a plain old extender it’s normal to see the throughput reduced to half or under. It’s also sharing the WiFi connection so that will effect performance and it’s on the same channel.
distance and interference also comes into play.
There are extenders that offer what some call fast Lane technology where the extender uses a seperate backhaul channel to keep throughput to max however they rely on 5Ghz so placement needs to be fairly close and if not place correctly devices hang on to either and will not swap. Some routers that over triband can use one of the extra 5Ghz channel purely for the backhaul thus improving the network performance.