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Visitor

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2 Messages

Thursday, October 20th, 2022 12:30 AM

Closed

Netgear NightHawk CM2000 firmware / slow speed issue.

First before I get started, I checked all my 2.5 GB cat 6 lan cables, my computer can max out 2.5 Gbit from another local system on my switch.  My router has wan and a lan that is 2.5 Gbit hooked to a trendnet 2.5 switch along with my computer having a 2.5Gbit nic.   I used to get 1.2 Gbit speed from my xfinity connection when I checked around a month ago.  I checked all my internal RG6 cables with a open/short tester, and no issues.  I hooked my cable modem directly to the line coming in from the yard and got the same results of 700Mbit/s. 

Problem:

A couple days ago I started noticing issues with a slower speed speed than I'm used to, so I checked the netgear night hawk cable gui page at 192.168.100.1 which showed a poor connection on my down stream.  After testing with speed test and xfinity's speed check, my internet connection is only running at about 700 Mbit instead what I used to get 1.2 Gbits, so I tried getting support on it from Xfinity. Support told me that my modem wouldn't accept the latest firmware.  I asked Xfinity support for the version of firmware they are trying to update it with and directed me to netgear support.  They either didn't know or wouldn't give to me.  I mean getting what firmware version should be and that they are actually updating it to is very important part of troubleshooting the issue.

So going forward does anyone know what the actual version my firmware should be on my Netgear Nighthawk CM2000? 

My modem reports V8.01.02 and the netgear site also says this.
https://kb.netgear.com/000036375/What-s-the-latest-firmware-version-of-my-NETGEAR-cable-modem-or-modem-router .  but doesn't mean it is the correct version that Xfinity currently using as they could be pushing out a new update. 

Right now it's either the issue support is saying, the firmware upgrade problem which they are telling me to go to netgear support which netgear will probably tell me to go back to Xfinity, and go into a support loop, or the issue is poor connection the modem gui is actually reporting on the downstream.  Does anyone have a suggestion on how to proceed for this problem as I pretty much eliminated any internal coax and network issue? 

Contributor

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14 Messages

2 years ago

Did you try to call Executive Support Team if everyone else is doing the run around game? <Edited: Forums Guidelines>

Typically the big wig support reps up there get things fixed and know way more than the lower level guys and clearly you know your network and your modem.

As for Netgear's website, they report that the current Comcast firmware is what you are on. There is always the chance that the quality issue isn't in your coax or your house but outside of your house, as happened with my internet a while ago, we had a squirrel damage the wiring causing the speeds to drop as low as 30MB/s. Comcast ended up sending a tech out to inspect the lines, found the damage to the exterior wire and had to run a whole new cable from the pole to the property.

(edited)

Visitor

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1 Message

2 years ago

No suggestions unfortunately. I'm having the exact same issue and it's not the first time. The same thing happened when I had a netgear nighthawk CM1200; everything was working great until Comcast pushed out a firmware update, and then everything went down hill. I replaced the cm1200 with the cm2000. I should have forseen the same issue occurring with another netgear nighthawk series... 

New Poster

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4 Messages

@darkbluman​ Yes.. I also moved from CM1200 getting speeds of 800 ish.. to CM2000 and now suddenly getting speeds of 550.  Someone needs to come in like Apple did with OS and allow companies/users to control the firmware.  I called Xfinity support and was told “we see ‘software errors’ on your modem.  I am tempted to borrow my neighbors modem to see if I get the same 1Gbps speeds he gets using the Xfinity provided modem to prove it isn’t outside lines.  They just ran a new line for me like 2 weeks ago.

Official Employee

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2.2K Messages

2 years ago

Hello, @Arthon. Thanks for reaching out for assistance with your internet speed. We want to ensure things get working up to speed once again. You would get firmware updates from your manufacturer. Have you checked for firmware updates using your router's administration site or consulted your user guide?

New Poster

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2 Messages

2 years ago

I have been having the same issue for going on 4 weeks.  Have had techs out twice and have been on the phone (or the gatekeeping assistant) for days, if hours were aggregated.  Currently waiting for someone to call me from the technical area.  All splitters have been removed, the connection to the house has been reworked and the lines physically inspected.

I went as far as replacing my 2 year old CM2000 with a new one yesterday to have the exact same issues.  So it is not the hardware.

The technician yesterday showed me that the SNR that Xfinity is seeing is higher than what the modem is seeing - and I suspect that this may be the big issue - the signal needs to be amplified.  All of this started when I cancelled my Xfinity TV service.  According to the technician. theoretically there should be no impact on signal strength...but clearly there has been (or someone turned down the signal at the box at the same time that cancelled the cable TV). 

Frustrated does not even begin to explain how this is making me.  I have had Xfinity for over 6 years and have had no internet issues until now - but the run around that I have been given over the past 3 and a half weeks is ridiculous.

Problem Solver

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892 Messages

Hi there @jabirdv! I am sorry to hear that you are also experiencing issues. By chance, did you get that call from our tech support? 

I no longer work for Comcast.

Visitor

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3 Messages

2 years ago

I am having the same issue! Using a Netgear CM2000 with Xfinity's Gigabit 1.2 Gbps service, but I'm only getting 600 Mbps tops. Most tests are actually in the 400-500 Mbps range.

I bought the CM2000 as a replacement for the CM1000, which was getting over 900 Mbps out of the same line just yesterday, so this really has me confused. I've called Xfinity support several times, and they tell me to reach out to Netgear, who then tells to call Xfinity. It's a nightmare.

When I look at the modem's diagnostics, it says the "downstream power level" is bad:

  -  Downstream Power Level: Bad
  - Downstream power is poor (17.2dBmV). The recommended level is between -10dBmV to 10dBmV.



Also had these error codes:

Mon Nov 21 16:22:43 2022 (Notice (6)) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;
Mon Nov 21 16:22:36 2022 (Notice (6)) TLV-11 - unrecognized OID;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;
Time Not Established (Notice (6)) Honoring MDD; IP provisioning mode = IPv6
Time Not Established (Critical (3)) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[REDACTED];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

(edited)

Expert

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107.1K Messages

2 years ago

@user_9010f0 

Please redact all of the CM MAC and the CMTS MAC addresses in your error log entries for your privacy. They are considered to be personal information. The posting of personally identifiable information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically. It flagged your post as "Private".

Visitor

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3 Messages

@EG​ Sorry about that but I think it's good now!

Visitor

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3 Messages

2 years ago

I was able to fix the downstream power levels to get them back into an acceptable range. Now everything is showing "green" for the CM2000. But my speeds are still only in the 400-600 Mbps range.

Here is the event log after another modem reset:

Time Priority Description
Tue Nov 22 09:39:28 2022 (Notice (6)) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;
Tue Nov 22 09:39:21 2022 (Notice (6)) TLV-11 - unrecognized OID;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;
Time Not Established (Notice (6)) Honoring MDD; IP provisioning mode = IPv6
Time Not Established (Critical (3)) No Ranging Response received - T3 time-out;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;
Time Not Established (Critical (3)) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;
Time Not Established (Critical (3)) No Ranging Response received - T3 time-out;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;
Time Not Established (Critical (3)) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;

Official Employee

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2.8K Messages

Hello and thank you for reaching out to us here on our Xfinity Forums. We truly appreciate all the troubleshooting that you have already attempted. Can you clarify how you are connecting to the internet when you run the speed test? Is it via Wi-Fi or an Ethernet connection? Is there a stand alone router as well as a modem in use? 

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

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2 Messages

2 years ago

To fix the issue, I went the route of least resistance because I know that Comcast wants you to use their modem, and cares very little to help out with these issues.  Using their modems, I would relinquish control over my home network, and even my home network privacy no matter what the policies they have in place as they change options in the config back every time there is a modem/router updated.  I continued to troubleshoot and kept wasting time going no where with testing the wires and modem resets to default, so I just threw money at the problem, and bought a Arris Surfboard S33, and while I don't like the design due to heat issues, I never had firmware or bandwidth issues in the past with an Arris modem. I just attach a 120mm case fan to the side to keep them cool, and Arris modems last forever.  My speed went back up to 1.2 Gbits/40Mbits once I switched it out which is what I'm paying the 70 dollars a month for 2 years.  Just annoyed I had to waste 150 bucks on the Netgear, but I would rather pay that than use a Comcast modem.

(edited)

Visitor

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1 Message

@Arthon​ Was just reading through this as I've just experienced my first CM2000 issue after activated it about 12 hours ago. It needed to be reset and I'm continuing to monitor it. Was curious: Are you using Cat6A cables or regular Cat6 cables? When I first turned on my CM2000 with a regular Cat6 cable plugged into the router, the multi-gig light was white indicating a 1Gbps connection. When I swapped the cable going from the CM2000 to my router and rebooted the modem, the light was blue indicating a 2.5 Gbps connection.

Visitor

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3 Messages

@surferdrew_84​ This is an interesting response, I'm on this forum cause I just bought a CM2000 after struggling with Xfinity's forced firmware push on the MB6811 (look at those forums for that Motorola modem, apparently it's a huge issue that both Motorola and Xfinity have no interest in fixing) so anyway, here I am wondering what problems I can expect upon receipt of my new modem. I've always found it interesting that Comcast is so dimissive of other provider's modems. I get that they want to push their own hardware and grow their voice / mobile phone service thanks to that mesh but I wish they also cared more about their customers when they choose their own equipment. 

Anyway, at least now I know to keep an eye on this. I'll buy some Cat6A cables. 

Visitor

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3 Messages

@Arthon​ Same - I refuse to use Xfinity's hardware. Never will I ever, unless you know, I'm on a deserted island and that's my only choice towards internet service. A few years back I had a problem with their modem, techs came out 2-3 times, service fees were paid for out of pocket for those techs to come out and still it was never resolved. Had a competitor (RCN - an east coast provider) come out, tech looked at the DB levels on the cable coming off the street and said that had to be tweaked and it was something easy, any tech should be capable of doing. He added some kind of splitter to my cable and things worked beautifully with my own Arris modem and their service. 

Returned Comcast's hardware at one of their locations, canceled the service and moved on. 3-4 years later, my credit report shows up with a $50 dollar collection for not returning their modem - so it created an additional issue I had to contend with. Unfortunately now I once again have the Xfinity noose around my neck as there are no competitors in my area but I refuse to use their hardware ever again and the sad part is, if they would just put in a bit more effort towards putting the customer first, I'd gladly pay them (or any corporation with good service). 

So what's your speed looking like nowadays? it's 4 months later so wondering if you ever got to that higher bandwith. 


(edited)

New Poster

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4 Messages

@Arthon​ This is good to hear because I just ordered an S33 v2 few days ago.  

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