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Assumed Modem Connection Issues.

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Assumed Modem Connection Issues.

 At a loss what to do at this point.

 

A while back, I was having all kinds of issues with my internet connectivity. As it turns out, there was a line rebalancing in my neighboorhood which sent my hardware slightly out of spec.

After 6 technician visits or so, we finially got everything normalized. The tech added an amplifier, and tested every single line in the house for intrusion which might have been causing some of my issues. In summary, the house wiring and levels are near perfect according to the last, most knowledgable, tech that visited.

 

Now I have a new problem, that a few times every few mornings, I get some sort of network blip that kills my VPN connection to my office. Comcast phone support is usually no help, and the My Account app never seems to report any outages, but it DOES show my modem in a red state tempoarily after these blips.

Its not out long enough to break any Netflix or Spotify stream, but my VPN back to the office appears to be extemely sensative to these occurances.

 

At first I thought it might have been that I enabled IPv6 on my router, but after extensive troubleshooting and factory resets, I eliminated that as a possibility.

My connection is all wired, no wireless.

 

I want to blame the modem. I'd had an Arris modem in the past at another house with ZERO issues. I recently upgraded to this Netgear when my original problems started after the line rebalancing. I've read some other post of people having issues with the same modem on this same firmware, but I don't know if that is really the smoking gun or not.

 

Would appreciate any input.

 

Modem: CM1000

Hardware Version: 2.02
Firmware Version: V3.01.02

 

Router: RT-AC68U

Firmware: 3.0.0.4.382_18881-gf09c5d3

 

My modem connection stats and my most recent modem event logs. None of the logs are from today when I had the disconnect issue twice this morning.

Typically, I can go days and not get any uncorrectables. Or at least that used to be the case.

Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency

<tabindex=-1>Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 573000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enable BPI+
IP Provisioning Mode Honor MDD IPv6 only

<tabindex=-1>Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 12 573000000 Hz 2.7 dBmV 39.2 dB 1197195984 0 0
2 Locked QAM256 1 507000000 Hz 2.1 dBmV 38.9 dB 1230579276 103 446
3 Locked QAM256 2 513000000 Hz 2.1 dBmV 39.0 dB 1230589319 119 439
4 Locked QAM256 3 519000000 Hz 2.4 dBmV 39.0 dB 1230597425 122 471
5 Locked QAM256 4 525000000 Hz 2.5 dBmV 39.0 dB 1230606283 114 469
6 Locked QAM256 5 531000000 Hz 2.9 dBmV 38.3 dB 1230616166 120 460
7 Locked QAM256 6 537000000 Hz 2.9 dBmV 39.0 dB 1230623323 130 458
8 Locked QAM256 7 543000000 Hz 3.1 dBmV 39.4 dB 1230633148 130 444
9 Locked QAM256 8 549000000 Hz 2.8 dBmV 39.1 dB 1230743084 90 472
10 Locked QAM256 9 555000000 Hz 2.9 dBmV 39.3 dB 1230753900 103 438
11 Locked QAM256 10 561000000 Hz 2.5 dBmV 39.2 dB 1230761610 102 447
12 Locked QAM256 11 567000000 Hz 2.6 dBmV 39.1 dB 1230768784 80 462
13 Locked QAM256 13 579000000 Hz 2.6 dBmV 39.1 dB 1230778762 89 474
14 Locked QAM256 14 585000000 Hz 2.6 dBmV 39.0 dB 1230789768 90 464
15 Locked QAM256 15 591000000 Hz 2.0 dBmV 38.9 dB 1230797604 84 469
16 Locked QAM256 16 597000000 Hz 1.4 dBmV 38.7 dB 1230803775 81 473
17 Locked QAM256 17 603000000 Hz 0.5 dBmV 38.4 dB 1231102485 82 473
18 Locked QAM256 18 609000000 Hz 0.0 dBmV 38.4 dB 1231112832 77 477
19 Locked QAM256 19 615000000 Hz -0.2 dBmV 38.5 dB 1231119091 90 463
20 Locked QAM256 20 621000000 Hz 0.0 dBmV 38.3 dB 1231129875 95 458
21 Locked QAM256 21 627000000 Hz 0.2 dBmV 38.3 dB 1231135907 86 469
22 Locked QAM256 22 633000000 Hz 0.0 dBmV 38.4 dB 1231146797 76 478
23 Locked QAM256 23 639000000 Hz 0.1 dBmV 38.2 dB 1231156652 89 465
24 Locked QAM256 24 645000000 Hz -0.1 dBmV 38.2 dB 1231162325 90 465
25 Locked QAM256 25 651000000 Hz 0.0 dBmV 38.3 dB 1231244989 84 471
26 Locked QAM256 26 657000000 Hz 0.1 dBmV 38.2 dB 1231251643 92 463
27 Locked QAM256 27 663000000 Hz -0.1 dBmV 38.1 dB 1231262191 97 459
28 Locked QAM256 28 669000000 Hz 0.0 dBmV 38.3 dB 1231268989 93 462
29 Locked QAM256 29 675000000 Hz -0.3 dBmV 36.0 dB 1231276850 83 459
30 Locked QAM256 30 681000000 Hz -0.2 dBmV 34.7 dB 1231279915 91 454
31 Locked QAM256 31 687000000 Hz -0.5 dBmV 36.6 dB 1231284225 94 446
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 29 36500000 Hz 42.5 dBmV
2 Locked ATDMA 30 30100000 Hz 42.5 dBmV
3 Locked ATDMA 31 23700000 Hz 40.8 dBmV
4 Locked ATDMA 32 17300000 Hz 40.8 dBmV
5 Not Locked Unknown 0 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Hz 0.0 dBmV

<tabindex=-1>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 32 822000000 Hz -1.6 dBmV 35.3 dB 1108 ~ 2987 251762567 199126048 0
2 Not Locked 0 0 0 Hz 4.3 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked Unknown 0 0 Hz 0 dBmV
2 Not Locked Unknown 0 0 Hz 0 dBmV

 

Time

Priority

Description

2017-12-13, 10:38:14

Warning (5)

RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 03:07:19

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 03:07:12

Notice (6)

DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 .;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 03:06:52

Notice (6)

Honoring MDD; IP provisioning mode = IPv6

2017-12-13, 03:03:46

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:56:57

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:56:51

Critical (3)

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:56:43

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:56:42

Critical (3)

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:56:35

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:56:34

Critical (3)

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:56:21

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:56:20

Critical (3)

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:53:51

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:53:50

Warning (5)

MDD message timeout;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-13, 02:53:46

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-12, 21:43:02

Warning (5)

Dynamic Range Window violation

2017-12-12, 21:43:02

Warning (5)

RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-12, 21:42:54

Warning (5)

Dynamic Range Window violation

2017-12-12, 21:42:54

Warning (5)

RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-11, 14:58:32

Warning (5)

RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-11, 12:47:14

Warning (5)

Dynamic Range Window violation

2017-12-11, 12:47:14

Warning (5)

RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-09, 18:47:23

Warning (5)

RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-09, 16:15:57

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;

2017-12-05, 12:43:02

Warning (5)

RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:af:YY:ZZ;CMTS-MAC=00:01:5c:63:YY:ZZ;CM-QOS=1.1;CM-VER=3.1;