Video static and noise

When meeting with my group, my and only my video display is OK for a bit, then deteriorates into a staticky video mess.  My image is degraded on my screen as well as all the other participants in my group. Their images are all good.

I've reloaded Zoom onto my computer, but that has affected no change.  I've called Spectrum about the issue and they tell me my cable signal is clear and strong.  Spectrum suggested I contact Zoom for a solution but, since I don't have a paid account or subscription, I don't seem to have any grounds upon which to interact with Zoom technical support.  

Any ideas, anybody?