Maybe the joke's on me.
Moving furniture around and putting the Cable Modem, Router, DVR, TV, etc on an UPS I had to push the TV console/cabinet back against the wall and the connect everything. The cats love to short cut their room prowl by getting behind everything they can so they've been passing below the outlet on the wall that the Router was plugged into. "Hmm, says I, this feels a mite loose in the socket". (In my defense the Spectrum tech did the initial connecting).
So I brought out a short 6 outlet strip and put everything on it and on another wall outlet, this one on the far side of the TV plus I put a plant stand in front of that outlet. Now the critters have to detour around both and the WiFi has been stable today. Now who'd thunk it.