Earlier quoted context omitted.
gotta ask, just because i went through this with spectrum recently. have you grabbed an extension cord and tried connecting the modem outside at the drop for awhile? i hear you that your neighbor has the same issue. but if youre in. say a development by the same builder, or were all part of a comcast upgrade at roughly the same time .. and well… you both recently upgraded to 1.2(?) because that would be the latter ca…
I had an old 15+ year old line when I moved in. Helped my neighbor cut a few hundred of his monthly by getting xfinity and they ran a brand new drop for him. Then just recently they "upgraded" my line. But I don't have any splitter or filter its just a connector with a ground that attaches my home cable to the drop cable.
i think my inside wiring was done no earlier than 1991 , but maybe redone once since then and it looked pretty good but i found this on the back of a wallplate , just yesterday:
- expires in 6 months
the easiest thing to do is check it at the box and then if nothing else thats ammo for dealing with customer service “look, i connected at the drop and have the same issue its NOT my inside wiring.”
everything from that point back is their problem and they owe you bill credits until its fixed, so get the proof and go back with it.
in my case my modem worked perfectly at the drop :D so i unfortunately had some digging to do
its not practical to suggest someone on the internet go ripping open all their wall plates and checking every inch of inside wire or maybe even running a new one. unless it passes the drop test, and then yeah, thats what needs to be done.
but plugging into the drop will 100% prove whose problem this is. youre california so thats also good ammo for a PUC complaint, that you did that and proved its not your inside wiring and now theyre refusing to deal with it. maybe that will get it to the right person on comcasts end faster when they review it.