For a month my internet goes out several times every hour. I have a direct line to my modem/router. Four different technicians (and supervisor) have been to my home four times and a maintenance worker (for outside) once. The maintenance worker was needed because twice I was told the problem is “at the pole” and not in my home since I have the direct line to my modem/router. The problem remains and I am told there is nothing more they can do to resolve the issue. Also, they could not explain why my phone also goes out which they cannot blame on poor wi-fi.
I experienced these same issues in January 2018 for a month long period. The problem randomly stopped. During that period Comcast made four visits, replacing all lines to and within my home and a new Xfinity modem/router.
I am currently using a Nighthawk C7100V.
We still need the signal levels from the modem, which show things like number of bonded channels, downstream power levels, Signal to Noise ratio (SNR) etc. Those will help clue us in as to where the problem may lie.
I'm having the same problem lately. A couple of years ago this same problem was resolved when they replaced some equipment out on the poles in the area - probably distribution amps or related.