Visitor

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10 Messages

Tuesday, June 9th, 2026 1:20 AM

Nine weeks, two tech visits, one underground dig ... still 10+ T3 timeouts per day. Need real plant-side escalation.

I received a notification that an underground cable replacement at my service address  was marked complete. However, there is an unterminated cable lying in my yard with no end on it. The work appears to be incomplete or improperly closed out.

Additionally, my modem is still showing the same service failures I was experiencing before the cable work — multiple T3 timeouts daily, continuous profile reassignments, billions of corrected errors on downstream channels. The cable replacement did not resolve the issue, suggesting either (a) the new cable was never actually put into service and I'm still on the old failing line, or (b) the wrong component was replaced.

I need:

  1. A technician dispatched to verify whether the new cable is actually in service or whether the work is incomplete
  2. The unterminated cable in my yard either removed or properly terminated as a safety/property issue
  3. Continued resolution of my service issue, which has been ongoing for over six weeks


    Looking for help from the verified Xfinity team here, because tier 1 and chat support have run their course.

    The short version: I've been documenting continuous DOCSIS-level service failures since late April. Two tech visits and one underground cable replacement later, my modem still logs multiple T3 timeouts daily and the failure pattern hasn't changed. There's also a physically unterminated cable sitting in my yard from the recent dig, which makes me suspect the work was either incomplete or never cut over.

    Setup:

    • Arris SURFboard S34 modem (CM-MAC available on request via DM)
    • TP-Link BE6500 router (irrelevant, but mentioning to preempt the question)
    • 9-unit condo in Aurora, CO
    • Equipment is new and top-rated, fully functional

    Timeline:

    • Early April 2026: Service starts failing every 5-10 minutes. Initial modem diagnostics show upstream power maxed out at 53 dBmV (over the DOCSIS 51 dBmV spec maximum). T3/T4 timeouts and RNG-RSP commanded power warnings flooding the event log.
    • April 26: Tech visit #1. Replaced wiring and a splitter inside my unit. Upstream power drops to a healthy 46-47 dBmV and has stayed there. Genuinely good work on the unit-level issue.
    • Late April / early May: Service failures return, but the signature is different now. Upstream stays clean. Downstream channels start accumulating massive corrected and uncorrectable error counts, T3 timeouts return, and the CMTS begins continuously reassigning my upstream profile on channel 43 (OFDMA) — sometimes dozens of times per day.
    • May 14: Tech visit #2. No meaningful change to the problem afterward.
    • May 21 onward: Service progressively worsens. Specific downstream channels in the 585-669 MHz band start showing catastrophic error rates. Channel 29 alone has logged over 3 million uncorrectable errors. OFDM PLC corrected errors hit several billion. Multiple T3 timeouts daily.
    • Early June: I notice an account notification that an underground cable replacement was scheduled and marked complete. I never received a phone call or door knock. I find a cable lying loose in the yard with no terminated end, sticking out of the ground.
    • June 8 (today): Modem still logs 7+ T3 timeouts in the past 24 hours. Same downstream error pattern. Same profile flapping. Nothing about the failure signature has changed despite the cable work being marked complete.

    Current diagnostic snapshot:

    • Upstream power: 45.8-46.8 dBmV (healthy)
    • Downstream: Multiple channels in 585-669 MHz showing tens of thousands to millions of uncorrectables. OFDM PLC at 3.5+ billion corrected errors and ~39,000 uncorrectables since last reboot.
    • Event log: T3 timeouts every 3-4 hours; profile reassignments every 10-15 minutes on OFDMA channel 43.

    The signature points to plant-side impairment in shared building infrastructure or upstream of the building. Healthy upstream rules out unit-level wiring (already fixed by tech #1). Frequency-specific impairment in a narrow band is classic failing-amp or failing-component behavior. Progressive worsening over weeks rules out a transient.

    What I think happened with the cable replacement:

    Either the new cable was never spliced in / cut over and I'm still running on the failing original, or the wrong component was replaced and the actual failing piece (MDU amp? building demarc? something further upstream?) is still in place. The unterminated cable in my yard strongly suggests the work isn't truly finished.

    What I'm asking for:

    1. Someone authorized to look at the CMTS-side telemetry for my modem and confirm what I'm seeing (T3 timeouts, PMA profile reassignment history).
    2. Dispatch of a plant maintenance tech, not another inside-the-unit service call. Specifically authorized to:
      • Verify whether the new underground cable is actually in service.
      • Test signal at the building demarcation point.
      • Trace upstream into the plant if demarc readings are degraded.
    3. Completion or removal of the unterminated cable in my yard.
    4. Service credit covering the duration of degraded service. I've been paying full price for a connection that fails multiple times per day for over six weeks.
    5. A single point of accountability for resolution. I do not want to start over with tier 1 again.

    What I have:

    Screenshots of modem diagnostics across multiple dates (April 3, 22, 27, 28, May 2, 13, 21, June 4, June 8) documenting the progression. Full event log exports. Chat support transcripts and ticket numbers from prior escalations. Happy to share via DM with anyone who can actually do something with them.

    I've been patient, technical, and accommodating through this entire process. The escalation path through chat support has not produced resolution. I'm posting here because I know the verified team here can route this to the right place. Genuinely appreciate any help.

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Visitor

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10 Messages

4 days ago

EDIT/UPDATE:

I went out and inspected the cable Comcast laid more carefully and want to add this to the post because it significantly changes the situation:

The replacement cable is unterminated on BOTH ends. It's just sitting on/near the ground, both ends loose, with no F-connectors, no splicing, no termination of any kind. It is physically not connected to anything.

This means the underground cable replacement that was marked "complete" in my Xfinity account is not actually in service. I am still receiving internet service over the original cable that Comcast itself determined needed to be replaced. The work order was closed without the cable ever being cut over.

That explains why my modem diagnostics show zero change in the failure pattern since the work was "completed" — because no actual work was completed in terms of service delivery. The dig happened, the cable got laid, and then someone left without ever finishing the job.

(edited)

Visitor

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10 Messages

So to summarize the current state:

  • Comcast determined the cable feeding my service needed replacement
  • Comcast performed excavation and laid new cable
  • Comcast marked the work order complete
  • The new cable was never spliced or terminated on either end
  • I am still on the failing original cable
  • I am still being charged full price
  • My modem still logs multiple T3 timeouts daily, identical to before the "completed" work

I have photos. Happy to share via DM with any verified employee who can route this to the right team. This is no longer just a service quality issue — there's an abandoned cable on the property and a work order that was marked complete when the work was demonstrably not done.

Anyone from the Xfinity team able to help get a crew back out to actually finish the cutover and put the new cable into service?

Official Employee

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3.3K Messages

Good Morning, @user_wx4ao8  I truly appreciate the time and effort you’ve put into documenting this so thoroughly it’s clear you’ve been dealing with a very frustrating and prolonged issue, and I’m really sorry this hasn’t been resolved yet. I completely understand your concern, especially with the cable work being marked complete while there’s still an unterminated line in your yard and no improvement in your service. You came to the right place for assistance. Can you please send me a DM with your full first and last name along with your full service address so that we can get your concerns addressed.

 

Here are 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 "Start new conversation" (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
You must use the primary Xfinity ID

I am an Official Xfinity Employee.
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Visitor

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10 Messages

Ok, done. 
now what?
or did you want me to send a message to XfinityRichard and not actually 'xfinity support'?



(edited)

Visitor

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10 Messages

EDIT/UPDATE:

Layered on top of all of this: I have spent countless hours in chat support over the past three months; even having to explain to the techs that came out what was going on because they were sent out here blindfolded on the issue...they asked me what's wrong as if I never relayed the enormous amount of detailed info to chat support. I walked them through the exact diagnostics - T3 timeouts, RNG-RSP commanded power warnings, profile flapping on multiple channels, frequency-specific impairment in the 585-669 MHz band, healthy upstream confirming the issue is plant-side, the whole thing. I came in with diagnoses, not just complaints. I asked for specific things; demarc testing, plant maintenance escalation, an actual cutover and documented every interaction.

Three months later: not resolved.

For context, I'm an IT sys admin and infrastructure architect by trade. If I left a critical production issue dangling for two months while making my customer do my diagnostic work for me, I would be fired. If I marked a ticket "resolved" when the underlying work was never completed, I would be fired faster. This is a multi-billion dollar company with plant maintenance crews, RF engineers, and CMTS telemetry on hand and somehow the customer doing free remote diagnostics from his living room is the one who keeps moving the ball forward.

I have photos of the unterminated cable. I have screenshots of modem diagnostics across roughly ten dates spanning the full timeline. I have chat transcripts. I have ticket numbers.

An FCC complaint is the next logical step.

(edited)

Visitor

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10 Messages

And yall are deleting comment replies from other users now. Color me surprised.

Visitor

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10 Messages

1 day ago

Another update - June 11:

Looking at the modem telemetry from today, something interesting jumped out that I want to share because it actually paints a more sympathetic picture of part of Comcast while making the overall situation more frustrating.

Somebody on the network engineering side knows my modem is a problem child. Over the past several weeks I've watched the CMTS push multiple US profile config updates, DS profile config updates, and today a brand-new "Profile 13" attempt that was introduced and immediately abandoned (along with the return of the RNG-RSP commanded power warning). These are real engineering attempts to stabilize my service from the CMTS side. They aren't ignoring me. Somewhere there's an engineer or an automated system looking at my modem MAC and trying things.

But you can't fix a broken cable with software. They keep tweaking PMA profiles and the modem keeps failing because the underlying physical impairment is still there. The dig crew came out, ran new cable, and walked away without terminating either end. The engineers on the CMTS side appear to have no visibility that the physical work wasn't actually completed - they're still trying to engineer around a problem that was supposed to be fixed days ago.

Also, a tech replied via the DMs about 45mins afterward I DM them:
"Thank you for reaching out to us directly, and I appreciate your patience along the way. Here on the Forums, we aren't an instant chat, so you may see time between some replies. I can assure you, however, we've gotten your message and we here to help. 
To start, I just need to complete a quick authentication step with you. I’ll send a time‑sensitive, six‑digit code to either your primary phone number or the primary email we have on file. Once you receive it, you’ll have 15 minutes to send it back so we can move forward.

Which do you prefer? text message or email?"

This is a multi-billion dollar company in 2026 by the way.
Am I expected to sit here for an ~hour waiting on a reply and then another for the text code? 
For experimental and curiosity purposes, I will, but do you all think every customer just has the allocated time to spend hours just to get connected to a tech? I am assuming I will get the same run around and be asked to explain my situation for the 16th time as if they have 0 notes taken from the previous and numerous chat transcripts, work orders, tech call-outs, tickets, and the existence of this forum thread.

I am currently 30mins in; waiting for this text code, after I replied "text me" .
Let's see where this goes. Stay tuned.

Visitor

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10 Messages

Got through the text code and was told:
"Perfect, we are all set. I am grateful for your help along the way. While in the account, I see you've been a customer in *STATE* since 2017. I wanted to take a moment to acknowledge your many years of business, as well as, all the additional troubleshooting/diagnostics you've completed on your end. I was checking on the notes from the last ticket where a drop order was submitted, which you've mentioned in your post. If you've found that the work was completed, but the new drop wasn't terminated on each end. We can certainly get a tech out to address this portion of the work as we work to improve your network health and connection. "

To which I showed them the screenshot of the work order and then images of the cable they mentioned "If you've found that the work was completed, but the new drop wasn't terminated on each end."

I don't mind sharing those images so here they are:
See the orange cable on the right and one going into the box full of cables/splitters. Both ends raw, not terminated.... 5 feet apart.




I also sent the text below with the images:
"Even if you all terminate both ends. the one outside the splitter box goes no where. its literally 5 feet away from the other end. What does the work order say was supposed to be done? 
Shouldn't techs take pictures once done a job?
Not to mention how spaghetti and unprofessional the inside of this box looks."

They replied:
"When we run a drop, the goal is to ensure it's routed correctly to the home and tap, so we want to get this addressed. Also, thanks for the photos. It helps give us a better picture as we report back to the local techs. For the visit, we need someone 18 years or older to be present. The work will likely mostly occur outside, but we do ask that pets be secured and that the tech has a clear path to each outlet if needed. Is there a certain day or time that works best for you? Can I also have the best contact number to provide for the visit? "

I provided the info. Will update as warranted. 

UPDATE: they scheduled a work order for someone to come out and look at the issue. I followed up asking, whats the plan and where is the cable supposed to go or replace?


(edited)

Visitor

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10 Messages

UPDATE:

I had a few practical questions before the appointment, including:

Will I lose internet during the work, and for how long?
What do the tech's instructions actually say about where this cable is supposed to go? Right now it terminates about five feet away from itself, going nowhere.
Is the new cable meant to be fed into the garage where the other connection box is?
Will the tech show up actually knowing what's going on, or am I going to be explaining everything from scratch for the 16th time?

The first internet question got a quick reply ("I believe you may for a short period of time") and an offer to reschedule, which I declined because I'd rather get this done while I have a hotspot ready. Fair enough.
But the questions about what the tech is actually being told to do, and where this cable is supposed to terminate, went unanswered. The conversation effectively ended with "we'll follow up after the appointment."
So I'm going into tomorrow's visit with no insight into the work order, no confirmation the tech will arrive informed about the prior six weeks of context, and the same gnawing suspicion that I'll be the one explaining the situation to them on my doorstep... exactly like the previous two visits.
I genuinely hope I'm wrong. I'll update tomorrow with what actually happens. If the tech arrives, knows the history, terminates the cable properly into the right box, and my modem stats finally normalize, this whole saga ends and I'll happily eat the words above.

Official Employee

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2.9K Messages

 

user_wx4ao8 With the time and effort you've already invested into getting this connection issue resolved, I definitely understand where you're coming from. I confirmed that my coworker added detailed notes for the technician who is dispatched to get your Xfinity internet back up and running tomorrow. My team will keep our private thread open so we can follow up after the appointment and ensure everything is good to go. When you work with my team, we will stick with you every step of the way and follow up as many times as needed until you give us the green light that everything is working flawlessly :). I appreciate your patience and we'll talk again soon! 

 

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

 • 

10 Messages

6 hours ago

Update - pre-visit phone call:

Comcast just called to confirm the 2-4 PM service window for today. Within the same call, the rep asked me to explain the problem to them.

I declined. After three months of explaining this issue to every single person at Comcast I've interacted with: chat reps, phone reps, two field techs, the verified Forums team - only to have to start over every single time, I'm done providing free labor to fill in ticket notes that should already be there. If the work order they're dispatching the tech with tomorrow doesn't have the history, the diagnostics, the unterminated cable issue, the photos I sent yesterday, or any context from this thread, that's a Comcast problem. Not mine.

What this phone call confirmed is that the ticket system still doesn't carry context across handoffs. The Forums team escalated, scheduled the tech, and (presumably) added notes - but the field dispatch team that called to confirm the window had no idea what the visit was even for; I know because they started off asking if my internet was working, then if my modem is turned on, and finally 'what is the issue you're having today?'. They were trying to fill in the blanks by asking me, the customer, what to put on the work order.

This is the silo problem I mentioned earlier in real time. The Forums rep was helpful and competent. The dispatcher who called me appears to be operating with the same near-empty work order that the last two techs walked in with.

If the tech shows up not knowing what they're here for, it'll be the third time in a row a field visit started with "so what's the problem?" That's a process failure, not a customer education failure.

I'll update after today's visit.

(edited)

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