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Constant disconnects, drops, and modem restarts with perfect Up/Down levels...

New Poster

Constant disconnects, drops, and modem restarts with perfect Up/Down levels...

I've tried everything else I can with Comcast support. As all of you know, it's a joke. I've managed to get a technician out here to check the lines and they weren't able to find anything wrong from the box outside to my house. ( I imagine the issue is further upstream than that / a technical issue that has nothing to do with the signal...)


The problem we have is that several times per hour, our connection times out for about 3 seconds or so. Both my fiance and I work from home full time and both of us have jobs where we're presenting on conference calls for an hour + at a time. When we lag / drop connection like that every 5 minutes, it makes watching our presentations or even us watching someone else's incredibly frustrating. But to make matters worse, after several hours of those 3 second drops, the modem will crash and burn hard and do a full reboot which drops us for 5 minutes at a time. When I check the logs, I notice there's a reboot message being sent to my modem from a Comcast device upstream. This tells me there's likely some sort of monitoring system in place for when it detects too many problems on a downstream device. I get it, but good god is that annoying. 


That said, the signal levels all look fine. I'll post the images to that in a few. The SNR and power levels are all within scope. What I do notice, is that shortly after a reboot, the Correctables / Uncorrectables start to climb into the 4 digit range. This happens fairly quickly after a reboot but not always right away.


As for what hardware we're using, here are the details:


  • Arris SB8200 modem
  • Orbi RBR40
  • 20-ish devices on my network. Most of the devices are things like an XBOX or a WiFi adapter for an outlet. Only two people live here so we're never using more than two devices at once (TV and Phone or PC and Phone). And I've confirmed that the RBR40 can support many more than 20-ish devices without having issues. And beyond that, the issue persists even when we only have one device on the network.


Here are the steps we've already tried to diagnose the issue:


  • Plug a laptop with a gigabit port directly into modem. Connection still maxes out at 600mbps on the 1gbps plan. Connection still drops several times per hour. Same events in the modem logs.
  • Use a Comcast Gateway. We tried that. Same issues. Though even lower average speeds with the comcast Gateway. I don't remember which model we tried, but it was one that the XFinity store rep said was their newest / best model. 
  • Checked all cables in the house for tightness / corrosion. Zero issues there. Everything's as tight as Comcast's support queues. 
  • Verified there aren't any splitters in the home between the outside connection and the modem.
  • Technician visited on-site and checked all levels and verified everything looks good.
  • Tried a different wireless router, but as we eliminated the router being the issue with the direct connect troubleshooting step previously, that didn't help.

At this point, I believe we've confidently confirmed that the issue is outside of the house and likely outside of the line that starts curbside. This has to be an issue with Comcast and their connection higher up than just the box outside my house. 


For the love of everything holy, please, can someone actually fix this issue? My job is dependant upon having functioning internet, as are millions of other people's. But at this time, my internet might as well be non-functioning. I had a few Comcast reps try to tell me "Well, your internet is online right now sir, so there's nothing we can do." I'm sorry, but trying to get off on a technicality while your paying customers are unable to use the internet reliably is an absolutely scummy way to run a business. 


That said, I have ATT and one other provider coming this week to install service. I'll be testing them out and if I don't have issues with them, I'll be disconnecting Comcast service to my home entirely. I've also spoken with everyone on the street that I live on and they all experience similar types of issues and every single one of them (only 6 homes total) have said they'd be willing to switch to whatever service I find that's actually stable. 


Pictures of modem levels:





New Poster

Re: Constant disconnects, drops, and modem restarts with perfect Up/Down levels...

i also have a sb8200 and am experiencing a very similar problem. Rebooting the modem doesn't really help. Just happens again. But when i'm not connected with work vpn, everything seems ok.

New Poster

Re: Constant disconnects, drops, and modem restarts with perfect Up/Down levels...

Out of curiosity, do you have a Xfinity Flex (Comcast's streaming IPTV box that they offer for free) attached to your system?  I have determined that this is the souce of my router crashes.  If I disconnect that box, my router no longer crashes ever hour (or so).