At my residence near Richmond Virginia for the last year around noon I would get an outage for about 5 minutes.
I attributed this to an IP swap as it was consistent. I went ahead and upgraded to a Netgear CM500 modem from my 3 year old CM400 in prep for faster speeds in the future. This made no difference to the issue. In the last few weeks these outages have started occuring more randomly sometimes in the morning, around noon, multiple times in the afternoon. Usually no more than 3 in one day but atleast 1 a day. Modem resets during the outages do nothing and the xfinity site cannot see the modem when an outage occurs.
I suspect a greater issue I have asked some neighbors who seem may have a similar problem. My modem reports good levels but logs the outages as t3 and t4 timeouts. Any help is appreciated, the line to the house is new as of Fall of 2016.
I only started noticing the issues February 2019 when I started working from home 1 day a week.
Below is the signal levels over 1 day. An outage occured around 8:30am 4/6/2020 and again around 2:30PM 4/6/2020
Here is an Imgur link in the meantime of the pictures. https://imgur.com/gallery/yBJ96VF
Can't see your pics. Since you are a new poster, they need to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting them at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to them here.
Inspect the demarcation point coax connections outside the building. Symptoms are consistent with those connections being waterlogged and/or oxidized and/or loose enough that sunlight or daytime heat is enough to degrade the signal significantly because electrical resistance increases with heat.
If the demarcation point is not 100% enclosed in a grey plastic box about 6 inches square and 100% isolated from water & sunlight, it is not up to current spec and is due to be swapped anyway.
If all this fits your situation, describe the symptoms to tech-support including the fact that you found degraded cables/connectors exposed to the elements outside and they should roll a truck at no cost to you to fix it. Let us know how it goes... Best regards...
The connectors that you photographed and reseated tightly are not so bad but maybe not 100% perfect 100% shiny like I want to see.
The demarc and the box near the street each appear to have been hydro-seeded or sprayed reliably by irrigation system like at my old place. The photo inside the box shows that liquid/mud has penetrated at least once.
The big connector is loose from wherever it should be tightened but maybe you loosened it in order to check the cables and photograph. When you found the connectors, was the big connector thing near the bottom where it would be submerged if the box filled with water?
At least one visible cable outside the boxes appears to have undergone multiple space-shuttle reentries.
Reseating/retightening may appear to solve the problem for a while but it will be temporary. I am pretty sure a legit tech would swap every visible cable and connector. I see you photographed the far end of the cable near street too - cool - that is well beyond the call of duty. Everything from demarc outwards is owned by the ISP and is their responsibility to fix.
The signal stats are o/k but the error log entries indicate that something is going on. Perhaps there is noise ingress into the line(s) somewhere.
There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.
I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. They will be able to poll the CMTS to see whether or not everything is in the green zone, see your node / cable plant and modem health, and also see a history plot for the modem. You should get a reply here in your topic. Good luck !
I'm so glad you reached out to us here about the intermittent connection you are experiencing. I would love to take a closer look to verify the situation. Just reading over the comments here it sounds like we may need to get a tech out for repairs, and I can help you set that up! Please send me a private message with your first and last name, as well as your service address so I can assist.
To send a private message, click my name "ComcastTambrey", then click "send a message".
Thanks for the update! I'm glad to hear it has been much better since the reset. You may not need a tech at this point, but if you would like, I can still double-check your levels on our back-end to see if we still need to keep an eye out for issues or if you are in the clear! 🙂
hi - I thought i saw dried dirt on outside of the boxes and at least one cable - maybe it was from rain instead of lawn sprinkler. the 'reentry' comment was for a cable extending downwards vertically from the demarc - i see now from your comment that i was seeing the outside of a metal pipe. there could be water and corroded cable inside that pipe too. the fact that you saw a change in behavior after disconnecting/reconnecting the coax cables strongly indicates that the root-cause of problem relates to the demarc connections. Glad you are seeing an improvement. If the performance degrades again, you will know where to look and/or to point the tech! best regards.