CM1200 Internet Issues: Intermittent Slow, or Disconnection - Spectrum

[findcanary]

Repost: Moved from https://community.netgear.com/t5/Orbi-AX/CM1200-Orbi-AX6000-Internet-Issues-Intermittent-Slow-or/m-p...

Hi All! 

I appreciate everyone taking a quick read of this, and seeing where I can begin.  I subscribe to a gigabit internet package, however, I'm typically receiving 300-500mbs, at the router, however, once in a great while, I'll get 900+gbs.

**added Tested from Speed Test APP over Hardwire, in addition to the built in app on the AX6000 router. 

Always seems to work great when the technicians arrive, and they always say: You won't actually get 900, you should be happy with 600, or it's your custom setup and I should use stock.  I don't know if I have a line problem, a hub problem, or a hardware problem. I'm hoping to learn what to look for when internet speeds are terrible so I have evidence to show the technician.  

What happens: I'll usually notice slow internet, then do the speed test within the Orbi, confirm slow speeds, then I've made it a habit of checking directly against the modem *Hardwired, just to eliminate a variable. It's usually faster, but I think it's because the Okta Speed test (BuiltIn) uses a different server than the one I select manually on my computer.  

Hardware: 

Netgear CM1200 

Netgear Orbi AX6000 (3-pack) 

Cable Matters CAT8 1ft between router and modem (Same Results with CAT6A, CAT6, or CAT5E) 

Spectrum 1GB internet package. 

Can anyone help me read the modem diagnostics to know if there is something that stands out?  

Sorry, the logs are only a few hours long, I had to do a hard reset of the everything with the tech here.  

Thank you for all of your help!  

Startup Procedure

Procedure Status Comment Acquire Downstream Channel 441000000 Hz Locked Connectivity State OK Operational Boot State OK Operational Security Enabled BPI+ IP Provisioning Mode IPv4 Only ipv4Only(0)

Downstream Bonded Channels

Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables 1 Locked QAM256 1 441000000 Hz 9.1 dBmV 43.3 dB 0 0 2 Locked QAM256 2 453000000 Hz 9 dBmV 43.1 dB 0 0 3 Locked QAM256 3 459000000 Hz 9 dBmV 43 dB 0 0 4 Locked QAM256 5 471000000 Hz 8.9 dBmV 43 dB 0 0 5 Locked QAM256 6 477000000 Hz 9 dBmV 43.1 dB 0 0 6 Locked QAM256 7 483000000 Hz 9.1 dBmV 43.1 dB 0 0 7 Locked QAM256 8 489000000 Hz 9.2 dBmV 43.2 dB 0 0 8 Locked QAM256 9 495000000 Hz 9.2 dBmV 43.2 dB 0 0 9 Locked QAM256 10 501000000 Hz 9.3 dBmV 43.2 dB 0 0 10 Locked QAM256 11 507000000 Hz 9.3 dBmV 43.2 dB 0 0 11 Locked QAM256 12 513000000 Hz 9 dBmV 43 dB 0 0 12 Locked QAM256 13 519000000 Hz 8.9 dBmV 42.9 dB 0 0 13 Locked QAM256 14 525000000 Hz 8.6 dBmV 42.8 dB 0 0 14 Locked QAM256 15 531000000 Hz 8.5 dBmV 42.7 dB 0 0 15 Locked QAM256 16 555000000 Hz 8.1 dBmV 42.4 dB 0 0 16 Locked QAM256 17 561000000 Hz 8.1 dBmV 42.4 dB 0 0 17 Locked QAM256 18 567000000 Hz 7.7 dBmV 42.3 dB 0 0 18 Locked QAM256 19 573000000 Hz 7.5 dBmV 42.1 dB 0 0 19 Locked QAM256 20 579000000 Hz 7.4 dBmV 42.1 dB 0 0 20 Locked QAM256 21 585000000 Hz 7.5 dBmV 42.1 dB 0 0 21 Locked QAM256 22 591000000 Hz 7.6 dBmV 42.1 dB 0 0 22 Locked QAM256 23 597000000 Hz 7.7 dBmV 42.1 dB 0 0 23 Locked QAM256 24 603000000 Hz 7.8 dBmV 42.2 dB 0 0 24 Locked QAM256 26 609000000 Hz 7.7 dBmV 42.1 dB 0 0 25 Locked QAM256 27 615000000 Hz 7.7 dBmV 42.1 dB 0 0 26 Locked QAM256 28 621000000 Hz 8 dBmV 42 dB 0 0 27 Locked QAM256 29 627000000 Hz 8.2 dBmV 42.1 dB 0 0 28 Locked QAM256 30 633000000 Hz 8 dBmV 42 dB 0 0 29 Locked QAM256 31 639000000 Hz 8.1 dBmV 41.9 dB 0 0 30 Locked QAM256 32 645000000 Hz 8.2 dBmV 41.9 dB 0 0 31 Locked QAM256 33 651000000 Hz 8.4 dBmV 41.9 dB 0 0 32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0

Upstream Bonded Channels

Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 73 5120 Ksym/sec 17600000 Hz 37.5 dBmV 2 Locked ATDMA 74 5120 Ksym/sec 24000000 Hz 39.3 dBmV 3 Locked ATDMA 75 5120 Ksym/sec 30400000 Hz 40.5 dBmV 4 Locked ATDMA 76 5120 Ksym/sec 36800000 Hz 40.8 dBmV 5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV

Downstream OFDM Channels

Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords 1 Locked 0 ,1 ,2 25 662000000 Hz 9.2 dBmV 41.5 dB 1108 ~ 2987 88772375 76351701 571 2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0

Upstream OFDMA Channels

Channel Lock Status Modulation / Profile ID Channel ID Frequency Power 1 Not Locked 0 0 0 Hz 0 dBmV 2 Not Locked 0 0 0 Hz 0 dBmV

Extended Upstream Transmit Power

Enable Extended Upstream Transmit Power

Current System Time:Mon Feb 15 17:04:38 2021

System Up Time:01:32:34

Time Priority Description Mon Feb 15 16:57:34 2021 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2.;CM-MAC=38:94:ed:07:28:58;CMTS-MAC=00:01:5c:7e:6c:58;CM-QOS=1.1;CM-VER=3.1; Mon Feb 15 16:57:12 2021 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=38:94:ed:07:28:58;CMTS-MAC=00:01:5c:7e:6c:58;CM-QOS=1.1;CM-VER=3.1; Mon Feb 15 15:52:23 2021 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2.;CM-MAC=38:94:ed:07:28:58;CMTS-MAC=00:01:5c:7e:6c:58;CM-QOS=1.1;CM-VER=3.1; Mon Feb 15 15:51:59 2021 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=38:94:ed:07:28:58;CMTS-MAC=00:01:5c:7e:6c:58;CM-QOS=1.1;CM-VER=3.1; Mon Feb 15 15:48:18 2021 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2.;CM-MAC=38:94:ed:07:28:58;CMTS-MAC=00:01:5c:7e:6c:58;CM-QOS=1.1;CM-VER=3.1; Mon Feb 15 15:48:04 2021 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=38:94:ed:07:28:58;CMTS-MAC=00:01:5c:7e:6c:58;CM-QOS=1.1;CM-VER=3.1;

[FURRYe38]

Make sure your Speeds are good at the CM modem with a wired PC using Ooklas installable speed test app. Not there web page. Check different servers as well for Ookla. Different servers may exhibit different results. Find one that works best on a constant basis. On a wired connection with a good CPU PC, you should see near or just over 900Mpbs. 

Ensure LAG is disabled on the CM modem. 

Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Mod...

[findcanary]

@FURRYe38 ,So, my wiring is all hidden, I'm not sure what it's doing behind enclosed drywall.   So while I'd like to believe that it's a straight shot, I'm not sure.   So before I start tearing my walls apart (joking) fishing wires through the wall, I'd like to know if singnals look good coming into the modem. 

To be clear, I've tested from the Ookla app, using my ISP cloest location from my laptop running hardwired directly into the cable modem, with wireless disabled.   

As to this

"Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly."

The two technicians both respond to me that it's not great, but it's within range.   Which I have don't know what the means.  I just feel like they don't actually want to check or repair anything, and I don't know enough to prove otherwise. 

Specific to

"Ensure LAG is disabled on the CM modem"

I'm not sure what this is, maybe you can explain? 

[FURRYe38]

For LAG log into the modems web page at 192.168.100.1 with a wired PC and look for Link Aggregation. Disable if its enabled. 

Also post the version of FW that the CM modem reports as well. 

[plemans]

Your power levels are a touch on the high side but nothing out of spec, just not optimal. I've ran mine hot before without issues. Its when you start getting errors problems in the logs.  The only one I'd even slighly be worrried about is the ofdma downstream is having uncorrected errors. The rest look good and your logs looks solid. 

If you're going directly 

CM1200---->PC 

without the router connected, what speeds do you get? 

The built in speedtest in the app isn't accurate >500mbps. So I wouldn't trust it. 

I don't even trust the speedtest site as not all of the servers there have maxed out my connection at times. 

So try different speedtest servers on speedtest as well as different sites like dslreports or even xfinity or spectrums dedicated test site. 

[findcanary]

Sorry I didn’t see this for some reason :(. I’m still having intermittent issues. May I ask when you say my power levels are a bit on the high side, what could cause that? My guess is that it’s bad cables or other interference that causes it to have to push harder to connect. However, that’s a complete guess maybe you can educate me?

[plemans]

Power levels are a function of where you are in relation to the hub and whats in between the 2. 

If you're home is right next to a hub, then you tend to have higher power levels. Sometimes you need to bring the power level down with an attenuator/splitter. Or if your home is to far away from the hub, you levels tend to be low and can cause issues.

Levels should be -7.5dbmv to 7.5dbmv  for optimal levels. you're above that but its not causing errors. It potentially could cuase issues on the upload so you can always try adding a double or triple splitter into the line (with other junctions capped off) to see if bringing your levels down help or not.