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Modem CM1000 Connection Dropping

Hi Guys-

Just installed a Netgear CM1000 modem and are experiencing internet drops a few times a day. I didnt have the issue with my previous modem connected to the same line, same equipment etc.  Please see modem stats and event log below.  Any help is greatly appreciated.  

 

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 567000000 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 13 567000000 Hz 21.9 dBmV 42.6 dB 948234349 0 0
2 Locked QAM256 1 483000000 Hz 22.4 dBmV 43.6 dB 938956815 0 0
3 Locked QAM256 2 489000000 Hz 22.2 dBmV 43.7 dB 938967591 0 0
4 Locked QAM256 3 495000000 Hz 22.2 dBmV 43.0 dB 938976370 0 0
5 Locked QAM256 4 507000000 Hz 22.4 dBmV 41.7 dB 938987760 0 0
6 Locked QAM256 5 513000000 Hz 22.2 dBmV 42.4 dB 938997760 0 0
7 Locked QAM256 6 519000000 Hz 22.0 dBmV 42.2 dB 939016893 0 0
8 Locked QAM256 7 525000000 Hz 22.0 dBmV 43.1 dB 939026582 0 0
9 Locked QAM256 8 531000000 Hz 21.9 dBmV 43.1 dB 939043035 0 0
10 Locked QAM256 9 537000000 Hz 21.9 dBmV 43.3 dB 939053384 0 0
11 Locked QAM256 10 543000000 Hz 21.8 dBmV 43.1 dB 939062561 0 0
12 Locked QAM256 11 555000000 Hz 21.8 dBmV 43.3 dB 939073713 0 0
13 Locked QAM256 12 561000000 Hz 21.9 dBmV 43.3 dB 939083330 0 0
14 Locked QAM256 15 579000000 Hz 21.9 dBmV 42.8 dB 939095060 0 0
15 Locked QAM256 16 585000000 Hz 21.8 dBmV 43.1 dB 939104018 0 0
16 Locked QAM256 17 591000000 Hz 21.8 dBmV 43.3 dB 939115278 0 0
17 Locked QAM256 18 597000000 Hz 21.9 dBmV 43.1 dB 939170058 0 0
18 Locked QAM256 19 603000000 Hz 21.9 dBmV 43.1 dB 939179667 0 0
19 Locked QAM256 20 609000000 Hz 21.8 dBmV 43.0 dB 939190670 0 0
20 Locked QAM256 21 615000000 Hz 21.6 dBmV 43.1 dB 939200458 0 0
21 Locked QAM256 22 621000000 Hz 21.5 dBmV 42.9 dB 939211153 0 0
22 Locked QAM256 23 627000000 Hz 21.5 dBmV 42.9 dB 939222070 0 0
23 Locked QAM256 24 633000000 Hz 21.5 dBmV 42.8 dB 939232539 0 0
24 Locked QAM256 25 639000000 Hz 21.5 dBmV 42.8 dB 939242772 0 0
25 Locked QAM256 26 645000000 Hz 21.5 dBmV 42.8 dB 939260894 0 0
26 Locked QAM256 27 651000000 Hz 21.6 dBmV 42.8 dB 939270839 0 0
27 Locked QAM256 28 657000000 Hz 21.4 dBmV 42.6 dB 939281602 0 0
28 Locked QAM256 29 663000000 Hz 21.4 dBmV 42.6 dB 939291725 0 0
29 Locked QAM256 30 669000000 Hz 21.3 dBmV 42.1 dB 939300957 0 0
30 Locked QAM256 31 675000000 Hz 21.2 dBmV 40.3 dB 939305809 0 0
31 Locked QAM256 32 681000000 Hz 21.3 dBmV 42.6 dB 939308942 0 0
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 89 35800000 Hz 44.3 dBmV
2 Locked ATDMA 90 29400000 Hz 44.5 dBmV
3 Locked ATDMA 91 23000000 Hz 44.5 dBmV
4 Not Locked Unknown 0 0 Hz 0.0 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 33 762000000 Hz 20.0 dBmV 39.8 dB 1108 ~ 2987 12359000 11030 0
2 Not Locked 0 0 0 Hz 19.1 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 dBm
 
 
 
Time Priority Description
2018-03-15, 01:42:46 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:01:5c:8e:0c:5c;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 01:42:45 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:01:5c:8e:0c:5c;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 01:42:36 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 .;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:01:5c:8e:0c:5c;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 01:42:19 Notice (6) Honoring MDD; IP provisioning mode = IPv6
2018-03-15, 01:39:13 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:01:5c:8e:0c:5c;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 01:38:58 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 01:38:53 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:01:5c:8e:0c:5c;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 01:38:50 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 .;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:01:5c:8e:0c:5c;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 01:38:45 Critical (3) REG RSP not received;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:01:5c:8e:0c:5c;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
2018-03-15, 00:37:43 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:42 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:42 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:41 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:40 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:40 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:39 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:38 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:38 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:37 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:37 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:36 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:35 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:35 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:34 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:34 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:33 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:32 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:32 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:31 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:30 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:30 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:29 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:29 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:28 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:27 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:27 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:26 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:26 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2018-03-15, 00:37:25 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:9a:6d:29;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Expert

Re: Modem CM1000 Connection Dropping

The downstream power is way too high / out of spec. Is there a drop amplifier in the coax line leading to the modem ? If so, try bypassing it and see.



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Frequent Visitor

Re: Modem CM1000 Connection Dropping

Thanks for the quick reply EG- I do have it running through an amplifier, as I did with the last one..  I will bipass the amp and see if the problem persists..  

Expert

Re: Modem CM1000 Connection Dropping

Please post the signal stat figures again after you remove it.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
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Frequent Visitor

Re: Modem CM1000 Connection Dropping

Thanks- see below spects post removing the aplifier-

 

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 567000000 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 13 567000000 Hz 6.6 dBmV 42.6 dB 2031805 0 0
2 Locked QAM256 1 483000000 Hz 8.7 dBmV 44.6 dB 709544 0 0
3 Locked QAM256 2 489000000 Hz 8.5 dBmV 44.6 dB 718935 0 0
4 Locked QAM256 3 495000000 Hz 8.2 dBmV 44.1 dB 728317 0 0
5 Locked QAM256 4 507000000 Hz 8.4 dBmV 42.8 dB 737241 0 0
6 Locked QAM256 5 513000000 Hz 8.4 dBmV 43.4 dB 746639 0 0
7 Locked QAM256 6 519000000 Hz 8.4 dBmV 43.7 dB 756035 0 0
8 Locked QAM256 7 525000000 Hz 8.2 dBmV 44.1 dB 765795 0 0
9 Locked QAM256 8 531000000 Hz 8.1 dBmV 44.1 dB 775004 0 0
10 Locked QAM256 9 537000000 Hz 7.9 dBmV 44.2 dB 784590 0 0
11 Locked QAM256 10 543000000 Hz 7.5 dBmV 44.0 dB 793657 0 0
12 Locked QAM256 12 561000000 Hz 6.7 dBmV 43.7 dB 802911 0 0
13 Locked QAM256 14 573000000 Hz 6.6 dBmV 43.0 dB 812908 0 0
14 Locked QAM256 15 579000000 Hz 6.7 dBmV 43.2 dB 822004 0 0
15 Locked QAM256 16 585000000 Hz 6.7 dBmV 43.5 dB 831245 0 0
16 Locked QAM256 17 591000000 Hz 6.7 dBmV 43.7 dB 840748 0 0
17 Locked QAM256 18 597000000 Hz 6.9 dBmV 43.5 dB 850019 0 0
18 Locked QAM256 19 603000000 Hz 7.1 dBmV 43.8 dB 860277 0 0
19 Locked QAM256 20 609000000 Hz 6.9 dBmV 43.8 dB 869744 0 0
20 Locked QAM256 21 615000000 Hz 6.6 dBmV 43.2 dB 878836 0 0
21 Locked QAM256 22 621000000 Hz 6.6 dBmV 43.5 dB 888053 0 0
22 Locked QAM256 23 627000000 Hz 6.6 dBmV 43.4 dB 897741 0 0
23 Locked QAM256 24 633000000 Hz 6.4 dBmV 43.3 dB 906985 0 0
24 Locked QAM256 25 639000000 Hz 6.4 dBmV 43.3 dB 916650 0 0
25 Locked QAM256 26 645000000 Hz 6.4 dBmV 43.2 dB 925952 0 0
26 Locked QAM256 27 651000000 Hz 6.5 dBmV 43.1 dB 935492 0 0
27 Locked QAM256 28 657000000 Hz 6.1 dBmV 43.0 dB 945074 0 0
28 Locked QAM256 29 663000000 Hz 6.1 dBmV 43.1 dB 954521 0 0
29 Locked QAM256 30 669000000 Hz 6.0 dBmV 42.5 dB 963009 0 0
30 Locked QAM256 31 675000000 Hz 5.9 dBmV 42.3 dB 969350 0 0
31 Locked QAM256 32 681000000 Hz 5.8 dBmV 42.7 dB 974522 0 0
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 89 35800000 Hz 41.0 dBmV
2 Locked ATDMA 90 29400000 Hz 42.8 dBmV
3 Locked ATDMA 91 23000000 Hz 41.0 dBmV
4 Not Locked Unknown 0 0 Hz 0.0 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 33 762000000 Hz 5.3 dBmV 40.8 dB 1108 ~ 2987 114 0 0
2 Not Locked 0 0 0 Hz 6.3 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
 
Expert

Re: Modem CM1000 Connection Dropping

It's much better now. You don't need the amp. Not sure that this was the root cause of the problem, but live with it for a while now and see if it still happens.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Frequent Visitor

Re: Modem CM1000 Connection Dropping

Thanks EG!!  Will update if anything changes!!

Expert

Re: Modem CM1000 Connection Dropping

Please do.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
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Frequent Visitor

Re: Modem CM1000 Connection Dropping

EG- Issue was gone for a few days and just returned..  Connection dropping for a few seconds and than returning..  No error in the log..  Please see specs below and let me know your thoughts..  Thanks!!

 

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 567000000 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 13 567000000 Hz 6.7 dBmV 41.7 dB 4022345146 70 246
2 Locked QAM256 1 483000000 Hz 8.3 dBmV 44.6 dB 4057780115 1179 5294
3 Locked QAM256 2 489000000 Hz 8.0 dBmV 44.4 dB 4057776404 1220 5246
4 Locked QAM256 3 495000000 Hz 7.8 dBmV 44.2 dB 4057786776 1361 5200
5 Locked QAM256 4 507000000 Hz 8.0 dBmV 42.0 dB 4057796218 1387 5006
6 Locked QAM256 5 513000000 Hz 8.1 dBmV 44.0 dB 4057807193 1317 5123
7 Locked QAM256 6 519000000 Hz 8.0 dBmV 43.4 dB 4057816534 1426 5059
8 Locked QAM256 7 525000000 Hz 8.0 dBmV 43.1 dB 4057822019 1871 5474
9 Locked QAM256 8 531000000 Hz 7.9 dBmV 44.1 dB 4057938920 1434 5045
10 Locked QAM256 9 537000000 Hz 7.8 dBmV 43.8 dB 4057952706 1533 4908
11 Locked QAM256 10 543000000 Hz 7.4 dBmV 43.4 dB 4057957348 1337 4372
12 Locked QAM256 12 561000000 Hz 6.7 dBmV 43.6 dB 4057966187 1358 5117
13 Locked QAM256 14 573000000 Hz 6.8 dBmV 42.2 dB 4057980067 1388 5091
14 Locked QAM256 15 579000000 Hz 7.0 dBmV 41.3 dB 4057984905 1277 5171
15 Locked QAM256 16 585000000 Hz 7.0 dBmV 43.4 dB 4057997531 1294 4956
16 Locked QAM256 17 591000000 Hz 7.1 dBmV 43.7 dB 4058006581 1285 5392
17 Locked QAM256 18 597000000 Hz 7.3 dBmV 43.7 dB 4058440090 1138 4907
18 Locked QAM256 19 603000000 Hz 7.4 dBmV 43.7 dB 4058450715 1196 4513
19 Locked QAM256 20 609000000 Hz 7.3 dBmV 43.7 dB 4058463378 1564 6987
20 Locked QAM256 21 615000000 Hz 7.1 dBmV 43.5 dB 4058472616 1489 6500
21 Locked QAM256 22 621000000 Hz 7.1 dBmV 43.5 dB 4058483816 1588 6424
22 Locked QAM256 23 627000000 Hz 7.0 dBmV 43.5 dB 4058490858 1481 6223
23 Locked QAM256 24 633000000 Hz 6.9 dBmV 43.3 dB 4058502840 1681 7413
24 Locked QAM256 25 639000000 Hz 6.8 dBmV 43.5 dB 4058513993 1772 7341
25 Locked QAM256 26 645000000 Hz 6.8 dBmV 43.4 dB 4058607231 1731 7271
26 Locked QAM256 27 651000000 Hz 6.8 dBmV 43.2 dB 4058611649 1800 7546
27 Locked QAM256 28 657000000 Hz 6.5 dBmV 43.1 dB 4058623162 1757 7482
28 Locked QAM256 29 663000000 Hz 6.5 dBmV 43.2 dB 4058620876 1863 8105
29 Locked QAM256 30 669000000 Hz 6.3 dBmV 42.9 dB 4058629135 1714 7009
30 Locked QAM256 31 675000000 Hz 6.2 dBmV 41.7 dB 4058652351 1880 7943
31 Locked QAM256 32 681000000 Hz 6.2 dBmV 43.0 dB 4058653049 1904 7950
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 89 35800000 Hz 41.3 dBmV
2 Locked ATDMA 90 29400000 Hz 43.3 dBmV
3 Locked ATDMA 91 23000000 Hz 40.8 dBmV
4 Not Locked Unknown 0 0 Hz 0.0 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 33 762000000 Hz 5.0 dBmV 40.5 dB 1108 ~ 2987 181502663 6336 1
2 Not Locked 0 0 0 Hz 6.1 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
Expert

Re: Modem CM1000 Connection Dropping

The stats are good but there are three additional signal stats that can cause problems which can't be read by the modem. They can only be read from their end by them polling the CMTS (Cable Modem Termination System) at the local headend facility.

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.

You can call in and ask what these figures are. The Upstream Receive Power Level should fall within the range of -2dB to +2dB with 0dB being in the middle and perfect.

The Upstream SNR should be least 31dB, and the higher it is the better.

The ICFR should be no higher than 2 dB.

You could have an intermittent noise ingress issue in only the upstream channel(s) / return path only somewhere.

They will be able to see whether or not everything is in the green zone and also see a history plot for the modem.




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Re: Modem CM1000 Connection Dropping

OK- thanks EG- will call Xfinity and ask for those extra stats and revert back..  

Regards.