No Ranging Response received - T3 time-out

Spent another hour plus with a call center. The agent actually told me to call the new modem manufacturer and it I wasn’t too happy, having to reexplain that this would make it two new modems in a row with same error messages and that the problem with the modem was unlikely as T3 tends to be more incoming line related. Asked to speak with a supervisor where I was put on extended hold again. Then finally reexplained things once again and this time the supervisor understood what I was saying and offered to send out a tech tomorrow.

Given that the last in-person tech couldn’t even understand why I wasn’t receiving full upload speeds, my expectations are understandably very low.

No one, especially more tech-savvy individuals who work with networking and computers should have to go through all of these layers of red tape nonsense. This kind of thing (outsourcing to people who don’t really care or are incompetent) can’t save that much money after going back and forth this much, and also reflects poorly on Xfinity/Comcast.

Still waiting on tech but here’s the latest logs. No disconnects BUT it is an intermittent issue and I wonder after a certain amount of these critical alerts it floods the modem which causes them to reboot. I removed my MAC addresses but I think you get the picture. The US profile change is a new notice to me and not sure what to make out of it. Perhaps someone is on here reading this and trying to fix it on their end.:

While I was away, another tech showed up but I managed to get to him while I was pulling back at the house over an hour later. I gave him the details. He checked some lines running underground near the street and said the signals were good. He tightened the coax in the underground box. I told him my upload speeds and download speeds and he insisted that no customer modem could currently do that. I informed him I have a brand new Arris S34 and he seemed surprised. Showed him my modem logs which he didn’t seem particularly interested in seeing. He essentially (to paraphrase) told me that it tells him nothing.

He went to the house and he tightened the connection around a coax filter anyways (think it’s a MOCA filter?) although I don’t have any cable TV or DVR boxes.

My SNR was running from the low 40s to up to ~44 (sometimes higher) and are now almost ALL 43.4 dB exact. I assume him tightening the connections had something to do with this because I’ve never seen it before nor did I even realize that it was even possible.

However, the errors still exist. I asked him about the intermittent disconnections and he said it could be the result of someone else’s Internet in the neighborhood causing these issues, or what he referred to as “ingress.” He said he would check in with the local xfinity guy tomorrow morning and monitor what’s going on as he could probably determine any bad interference. And that’s it. He didn’t solve the underlying issue. Just tightened a few things.

Here’s the stats in case it helps. You can see how the SNR looks pretty decent (or so I think) after he retightened some connections:

Update: posted to Reddit since I’ve had 0 feedback or acknowledgment here:

https://www.reddit.com/r/Comcast_Xfinity/s/hY7HJyylJi

Additional update (posted on Reddit): noticed that the upstream power levels are consistently below Arris recommendations which are above 40+. Arris instructs techs to reach out to the cable providers in order to have the power increased. I brought this to an agent’s attention on Reddit and he confirmed that I was correct in this. But this may have nothing to do with the errors/disconnects that I have been receiving. Link to Arris’ documentation regarding S33 and S34 modems and power levels in the Reddit cross-post.

Xfinity has scheduled a supervisor tech to come out next week to take a closer look since the issues are still unresolved.

Hello user_rwc2zv, thank you for including such great detail in your post and for taking all of those steps on your end to try and find a solution to your intermittent connection issue. I hope your family is doing fine and everyone is healthy. I can only imagine what you've been going through, connection issues are always frustrating let alone going through it during those family emergencies. You've mentioned a few modems, so I'd like to review your account, confirm we have the correct device listed as active, check out your signal levels, and take any appropriate steps after. In order to get started can you please send a direct message to Xfinity Support with your full name and full address by clicking the chat icon in the top right? Here's the detailed steps to direct message us:

• Click "Sign In" if necessary

• Click the "Direct Message” icon (upper right corner of this page)

• Click the "New message" (pencil and paper) icon

• Type "Xfinity Support" in the to line and select "Xfinity Support" from the drop-down list

• Type your message in the text area near the bottom of the window

• Press Enter to send your message

@user_rwc2zv @XfinityMarcos 

Please circle back here and post any possible solutions for the issue here in these open public forums so that all readers here may benefit from the exchange / info. This is in keeping with the spirit for which these public help forums were originally intended. Thank you.

10/16/24 Update: Comcast Executive relations reached out to me yesterday and apologized that I had gone through stuff. He mentioned someone would reach out to me about a watch I was told was completely free as well as the line charge that turns out wasn’t while I had waited on the phone regarding this issue (one issue led to another issue…) He also offered to send out another tech agent to look at the modem but I mentioned that I was already waiting for the tech supervisor and local installer to potentially work on power to the tap and imbalances they found here.

Meanwhile, I had received the 12 db Return Path Attenuator yesterday and installed it at the modem. Of course I had unplugged it and it rebooted. The Upstream Bonded Channel values are now in perfect range of 45-50 dBmV (except the OFDMA which I read elsewhere is supposedly normal) with what Arris recommends for S33 and S34 modems. Downstream values are still the same as before which is what I had wanted (versus an ordinary attenuator or splitter.) It appears DOCSIS 3.1 modems almost always require higher power levels but depends on the manufacturer. However the T3 errors are still occurring. I counted 16 T3 critical errors yesterday alone after installing this so nothing really changed. I don’t know what this entails or if it’s normal.