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Thursday, February 22nd, 2024 12:00 AM

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Cable Modem Uncorrectable Errors, Notice/Critical Events in Log?

I've been battling Xfinity internet issues for years. I replaced the modem for a Netgear CM2050V, purchased a hefty pfSense router, and installed MoCA adapters (completely isolated from the modem's coax line). The internet appears to be rock solid, except for some irregularities reported by the modem and router.

The router’s gateway monitor has been reporting intermittent latency/packet loss. The issues have been too brief to cause any noticeable disruptions, but they’re noticeable for some applications. At any rate, it prompted me to look at the cable modem’s information. Here’s what I found:

I have no idea what I’m looking at, but the uncorrectable errors and various stuff in the event log seem concerning.

Anyway, the power company recently re-installed some sort of surge protector for the coax line after it had been disconnected twice by Xfinity. I’m thinking this is the culprit, assuming there’s an issue in the first place. I’m a little worried about calling Xfinity to check the line, though. The tech might blame the MoCA devices. I also want to avoid touching the cable modem’s coax line if I can, but unhooking the surge protector is such a simple thing to do.

So, I basically have two questions:

  1. Do I have a problem with the cable modem?
  2. If so, could the coax surge protector be the problem?

Thanks in advance.

Accepted Solution

Expert

 • 

110.4K Messages

1 year ago

This may or may not be the root cause of the problem (YMMV), but if you have an inline coax surge protector installed, remove it. They are not recommended. They are known to be troublesome. Comcast does not use them.

That said. The signal status values at that snapshot in time were OK / in spec, but the error log entries indicate that something is going on. Perhaps there is noise ingress into the line(s) /  an upstream channel / return path impairment somewhere. The CMTS / system is having some difficulty hearing the modem reliably so it is losing block sync.

There are other signal stat values 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 (The Digital Care Team) who are available to these boards. They will be able to poll the CMTS (Cable Modem Termination System) to check for any real-time degradation and / or error reports, see your node / cable plant, and modem health, and see whether or not everything is in the green zone. They can also see a history plot for the modem and those upstream receive signal stats.


You should get a reply here in your topic. Good luck !

Official Employee

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1.9K Messages

1 year ago

Hello, @thetallguyyy. I'm sorry to hear about the internet issues you've been experiencing even after purchasing a router and installing MoCa adapters. I'd be more than happy to review your account to see what we can do to help resolve this problem once and for all.

 

In order to get started, can you please send me a private message to Xfinity Support by clicking the chat icon in the top right?

4 Messages

@XfinityRaul​ Your name doesn't show up when I search for it.

Retired Employee

 • 

729 Messages

@thetallguyyy

 

To send a direct message:
Click "Sign In" if necessary
Click the "Direct Message" icon or  https://forums.xfinity.com/direct-messaging
Click the "New message" (pen and paper) icon
The "To:" line prompts you to "Type the name of a person". Instead, type "Xfinity Support" there.
As you are typing a drop-down list appears. Select "Xfinity Support" from that list.
An "Xfinity Support" graphic replaces the "To:" line.
Type your message in the text area near the bottom of the window
Press Enter to send it

Expert

 • 

110.4K Messages

1 year ago

@thetallguyyy 

You need to use the name Xfinity Support as he stated.

4 Messages

1 year ago

Oh right, sorry about that.

Expert

 • 

110.4K Messages

1 year ago

@thetallguyyy 

No worries ! 🙂 It was confusing.

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