Hi folks. This has been a really frustrating problem and, inspired by the eventual success of other threads like "No internet after midnight", I've decided to start documenting it here.
If anyone has any suggestions, please let me know! Otherwise I'm hoping I'll be able to use this thread to better communicate with Comcast tech support.
I live in Oakland, CA, and I've been getting good gigabit speeds from Comcast without problems for 2 years now. Then, starting sometime in January, the internet started going out sometimes in the morning. It normally goes down for 10-30 minutes 3 or 4 times each morning. It took me a while to realize what was going on because I'm normally not home at that time, but we are expecting a child in April so I've been working from home more mornings to be around for doctor appointments. I also installed a smart camera outside and it has been sending me disconnection alerts several times a morning for several weeks now.
The really weird thing is that it seems more reliable on weekend mornings. If it were *every* morning I'd suspect heat expansion from direct sunlight on some component. And it may still be that....maybe I just sleep in too much on weekends to notice it? But it seems like it could be traffic related or something like that...I have no idea.
What I've tried to fix it
I was using an Arris SB8200 modem connected to an Asus RT-AC86U router. As part of troubleshooting this problem, I bought a new Motorola MB8600 modem. It exhibits the same behavior as the Arris did, so I don't think the modem is to blame.
Ok, what about the router? Well, the router seems to work fine. I tried switching it out for a borrowed one and that didn't fix anything. And when the internet is down and I check Comcast's status page under my account, I do get a "We can't connect to your device" message and an indication that an issue is detected with the modem.
The weird thing is that the modem itself (both the Arris and the Motorola) thinks it is connected. All status lights stay on. It is talking to something. But Comcast's home office can't reach it and thinks it is offline. (I know this seems weird, but I swear it's true. I have contemporaneously time-stamped photos showing the modem and then the status page a few seconds later if you really don't believe me.)
If I power cycle the modem, it is generally able to reconnect after a few minutes. But then the internet normally goes out again within a few minutes after that. Even though the modem still thinks it is connected.
What Comcast has tried to fix it
I have called Comcast a few times over this and gotten a variety of responses.
Once I was told there was an unexpected outage in my area that should be fixed within a few days. Ok. But it's been a few weeks now.
Once I was told that they remotely reset the modem and everything was fine now.
Once I was told that they remotely resest the modem and it was connecting, but their diagnostics showed something unspecified was wrong with the line and they would send a technician the next day.
The technician was very patient and polite, but he was there in the afternoon and everything was working, and he couldn't find any problems. He tested the line, replaced a few connectors and a short piece of cable just in case, and recommended renting a Comcast modem in the future if it continued.
That was yesterday. The internet went out again this morning and it's been up and down as I'm writing this.
What should I do now? Any suggestions?
If fiber were available in my neighborhood, I'd switch at this point, but Comcast is my only option for gigabit speeds.
I'm planning to continue documenting the problem on this thread, as time permits (I don't have time every day and I'll have other things to do for a while after the baby arrives). And I'm planning to keep calling Comcast tech support every few days.
Thank you all!
I seem to be having the same problem in the San Jose, CA area since January, and I nailed it down to the modem receiving very low downstream power and resulting low SNR from the modem log/status page, when the disconnection happens. For me, the problem seems to occur between 3 pm - 8 pm, when the power degradation occurs, and then after a while the downstream power (and SNR) goes back up to normal/good levels.
I reported it to Comcast, the first rep arrived at a time on a Friday when this transient problem wasn't there. So he poked around and left, without solving the problem that occured a little later the very same day. The next rep. came on a Sunday after I raised the unfixed issue with Comcast again, noting it wasn't fixed, its transient and so on. This rep. said there is work being done outside in Comcast's lines/network, which should fix the problem - and then poked around my apartment again. There was no problem inside my aparment - this setup (hardware, wiring, etc) has worked flawlessly for 3.5 years after all.
The fact that it is transient during some times during the day, and goes away by itself - coupled with my noted low downstream power at the modem when the line degradation happens - indicates the problem is fully with Comcast's network/hardware outside. However, I'm appalled that Comcast is clueless about what could be the root cause.
I'm looking to seek help from knowledgeable Comcast folks, rather than being given the run-around by the technicians who seem clueless. Anyone can help ?
More details on mine:
My neighbor is apparently running into the same problem (further suggesting that this is something external within the broader Comcast network).
He said that recently he has been seeing a couple hours a day when his internet and TV both get spotty, normally in the morning.
On 2/29, this went out and never came back. A tech is coming out this coming Thursday, March 5. My neighbor will try to let the tech know that there is a broader issue in the area and that it's often transient. Fingers crossed.
He did say that Comcast ran some diagnostics from their side and thought they knew what the issue was.
Talked with a second neighbor. Her cable has been spotty for a month and she had a tech come out last Friday (Feb. 28).
The tech believes he traced it to a pinched cable on a newly replaced electrical pole up the street. PG&E replaced the pole a bit over a month ago, so the timing is fairly close.
He told my neighbor that Comcast will have a crew out to look into it and hopefully fix it on March 5. Fingers crossed this does the trick.
The behavior (going out at the same time each day) was likely related to heat expansion from direct sunlight in the morning hours, or at least that's the theory.
We'll see if the problem continues or if this resolves it.
Note how the timing of the failures follows sunlight/daylight. Impedance increases with temperature. Those of you seeing this sort of failure are likely to have your demarcation point be on the windward and/or sunny side of your residence. If you have an old demarc exposed to elements and not inside a plastic-box-with-accressible-door, you can consider to request comcast to swap for the new/better demarc - the tech will cut off the old corroded connectors & re-crimp new connectors & reconnect the cables and put it all inside the gray-or-green plastic box. You can inspect the demarc yourself and provide photo of any evidence of corrosion or tell comcast if you find loose connections. If the exterior cable-connections are anything less than 100% dry and are exposed to elements whatsoever, comcast going to swap it sooner or later as they are swapping them all across USA. Call them and be nice and ask them to swap it sooner. To be clear, comcast owns the demarc 100% and they will charge you z e r o to diagnose or swap it. They only charge money if they have to deal with your inside wiring/network. Also, consider to re-run your tests from the interior of your house as close to the exterior demarc as possible - with zero splitters - zero wifi - zero router - direct hardwire your computer to the cable modem temporarily in the basement if you are up for it. This testing method eliminates your inside wiring from being part of the problem and tests only the comcast-owned equipment. Pony up $10 to rent a comcast cable modem for the month to do the tests, if that helps to convince them. They will refund it after you & the tech & more testing & a corroded demarc prove what the root cause was.
While this could be the problem with temperature effects on Comcast's infrastructure, I can see no way to make the techs who come out to understand all of this you've stated. They are either ignorant or condescending/arrogant or both - when you can explain the transient nature of the problem. They also seem to be hyperfocused on pinning the problem on something "inside your home" (so that Comcast can charge for the tech visit, I presume). Speaking from experience on all of the above, with 2 tech visits.
That is the reason I posted here, hoping someone from comcast with knowledge and intelligence can help fix this.
Final update (hopefully):
Things have been stable again for the past week, so I assume whatever work they did out on the line did the trick.
Very grateful to all my neighbors for pushign this as well, since I think it normally takes a number of reports before they'll start looking into that sort of thing.
Wow this sounds identicaly to the issues we have had for months and still continue to have. At first Comcast determined it was the modem, then it eventually was elevated and determined it was massive interferance in the neighborhood lines. I talked to one tech after he climbed the poll and he found massive interferace and said he would fix it. The issue kept happening. Its less severe now, but still occurs 1-3 or more times a day. More tech visits and more areas they find interferance on their polls. Odd thing is they are showing the modem remains connected, when its been going down. Now its suggested that one of my devices in my network is the probelm. None of my neighbors have these issues as they are all on FIOS. I finally ordered Fios for internet and for the moment I have both services. Fios (direct fiber into the house) has been down zero times in two weeks and Comcast continues with these periodic randome drops. Service was fine and mostly reliable except for reported area outages for almost two years and then a disaster for about the last six months.