Packet Loss Hell: over half a year later and there's no hope in sight.

If it's upstream, it is Comcast's responsibility to check it. Their line of demarcation ends at the drop/tap. I'd call and say you have done testing and lay out what you've done and seem to have recurring upstream signal issues. The person you talk to should be able to check your signal levels from afar and the history of your signal levels for weeks back, how many timeouts and resets and lost syncs and upstream/downstrean errors you've had and it should be fairly obvious you have an intermittent signal issue. The problem with these are that they are notoriously hard to nail down, it's not like it's a flat cut cable and it's obvious where it is. It could be wear and tear at any point along the line from the headend to the drop, to the tap on your house, to the internal wiring in your house, to a problem with the outlet jack your modem is plugged into. It could be old equipment, it could be the house next door has bad unshielded wiring and is emitting noise on their cable network that is interferring with yours without stopping it altogether, it could be something as simple as high humidity sometimes causing water to form somewhere it interferes. I'd call Comcast and say you'd like a technician to come out and check your signal issues. If the tech comes out and determines the problem is not your actual modem but something outside the house, they should put in a job for a more advanced network technician to trace the signal from your house to the headend and see where the interference is coming from or if they can't determine it right away they'll send a technician out to check all the sites along the cable network that may be interferring with you. Be polite and insist on a technician coming out, ask to escalating the issue, ask to speak to a supervisor if necessary. If you've called many times, be sure to reference ticket numbers, or say that this problem has NOT been solved and please look at your ticket history. No matter even if your internet comes back fine after just a few minute, always call it in. This way there is a record of your signal problems and Comcast will have a record of times, dates, troubleshooting they've done, etc. I hope this helps.

/r/Comcast Thread Parent