The neighbor would often complain about his cable and ask if I had the same problems. I did. One day, he'd had enough, and switched to DSL and satellite.
Sounds like fitting either house (or ideally both) with a $15 POE filter from Amazon would have fixed the problem.
(POE in this case is point-of-entry not power-over-ethernet.)
I had to get one to make MOCA (ethernet over cable) work in my current house.
I had to get one to make MOCA (ethernet over cable) work in my current house.