I am getting the wifi signal drop out all the time (as too slow) when trying to stream from my PC upstairs to TV (Firestick) downstairs. Via cable (into PC) my speed is excellent 198 mbps. There aren't any major obstructions, just a couple of walls. Used to be OK but just started happening. Is it the router? - any ideas
Can't see your image yet but I'll respond. If it has only just started to happen then it is most likely to be something causing interference to your Wi-Fi signal. The source could simply be a neighbour who is on the same Wi-Fi channel as you or it could be from any sort of household appliance (yours or neighbours') that transmits radio frequencies (smart meters, heating controllers etc.)
Try changing the Wi-Fi channel in the hub's management interface ... there's a video tutorial at the top of this forum.