So basically I had a old 3.0 modem that worked fine until the end of February and it started losing internet signal so I would unplug it and plug it back in and it would work fine. It would happen once or twice a day not to much of a big deal. But after around the beginning week of March it would constantly cut out and I started getting mad and called Comcast they told me that my modem wasn't going to be supported after awhile and that that might be the issue. Next day i bought a new modem Arris sb8200 because it was on the page on Xfinity that would work with my internet plan and for the first three days it worked fine then boom constant drop and even worse. We had a tech come the next day and couldn't find anything wrong until he check the signals on his phone and found the problem. He told me that maintenance would be their Monday to fix the problem. Monday came their was a Comcast van outside but I didn't seem like they were here for the fix but I still was having trouble with the internet and we ended getting a supervisor to come out and check are equipment and all that. He came and did help me get my speeds back on track but the problem with my internet getting disconnected I was told that maintenance had to come fix and that they were finally able to put in a ticket in to get it situated so I was like cool and what not. I saw people outside like two days after from some company called OCC fixing a line that I would assume was bring noise into the line and probably was what was causing the problem. Even with that the issue wasn't resolved I still get internet drops not badly like before. I ended up buying a new coaxial cable to see if that could help but no. Am starting to think it might be my modem but at the same time if it was happening with my old modem. I don't think it that. I keep getting on my Arris reports of t3 and t4 timeouts and sometimes something about started unicast maintenance. I don't know what to do and am tired of having this problem anybody know what I can do I will post my event logs and what not but please am tired of this BS.
Whatever your issue is I also have it on my line as of today (3/29/19). It just started maybe an hour ago or so. So it may be an issue affecting the whole network. I know for a while on my device (gateway/combination modem and router, model SBG6580) they had pushed a bad firmware to it and it would cause HOURS long outages. Yet for some reason the outages would only occur in the overnight hours. Very unusual. They eventually rolled back the firmware until it could be fixed and then re-released it once it was corrected.