I have set the hub to from 2.5/5 ghz our alarm and solar panel system will only support 2.5ghz, we are fibre optic to the premises we have all had our installation at different dates over the last 8 months, it was poor before the fibre optic it is hit and miss now.
The speed to the hub is excellent, the speed from the hub is slow and unreliable, BT only guarantee the speed to the hub, after that you are on your own.
Unfortunately I have suffered a brain injury and occasionally I get confused and often say the wrong thing.