The wifi perfornance is variable and often very slow. I am familiar with networking, having been a radio ham for many years. Previous performance with the ADSL2+ Thompson router was good. The wifi was very solid and reliable, matching the 8Mbps download wired.
Nothing has changed here. I live in a rural area overlooking miles of countryside. I have only one neighbour, whose BT wifi is on channel 11 and I have set my wifi on channel 1. The performance in my house (very old, thin walls, no metal) is poor even from only one room away.
The only use for the wifi is Chromecast occasionally, my wife's notebook, and a couple of mobiles and a tablet. No kids or any real demands on the wifi.
My conclusion so far is that the supplied Sagem modem is hopelessly inadequate and cheap, OR there is a fault (which given the wired performance is less likely)
Any advice from anyone on what I could try?
I might go and buy a TP'link 1750AC for £89 if I have to, but I am not sure whether this just plugs into the BT modem in place of the Sagem, or whether it replaces the BT modem as well.
(ignore previous location below)