If the ethernet connection remains ok and so it turns out that it is a wifi issue and not a network connection one then on a Hub3/4, try separating the SSID's of the 2.4 and 5 GHz wifi bands by renaming them in the settings and at the same time switch off "channel optimisation" Then use a wifi scanning App to find the best wifi channels to use (just use 1,6,11 on 2.4GHz)— that often helps Hub3 users get better wifi performance - but its still no substitute for getting better kit 🙂