Yep, it is a thing. They are attracted to the metal in the coax from your home to the pole.
I messed around for about a year trying to figure out intermitent problems. After a second Xfinity tech visit (he was also the first), the tech sheepishly said to me “I should have checked your wire to the pole. It was totally chewed to shreds. I have never seen such a badly chewed wire!”
So, the lesson is this: When you have connection problems with any DOCSIS based system and you have wires to the pole and squirrels, make sure the tech checks the outside wires!
New coax fixed it.
Hi, tsakmok. Thank you very much for taking the time to post this. It definitely helps out the community here. You are right about squirrels checking coax, it's definitely a thing! Happy to hear your issue is fixed. Thanks again, take care!