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Network Speed Slowdowns

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Network Speed Slowdowns

Hello,

 

I am slated for the 600 MB/S  download plan with xfinity, but recently have been experiencing slow downs t around 25-50 MB/S download. I have checked my Modedm (Netgear CM1100, Firmware Version V6.01.07) logs and found the following:

 

Time Priority Description
2020-05-10, 12:33:08 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3;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-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-05-08, 07:09:33 Critical (3) Resetting the cable modem due to docsDevResetNow
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-outCM-QOS=1.1;CM-VER=3.1;
2020-05-06, 06:52:56 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-05-06, 06:51:51 Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
2020-05-06, 06:49:51 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-QOS=1.1;CM-VER=3.1;
2020-05-06, 06:49:46 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-QOS=1.1;CM-VER=3.1;
2020-05-05, 11:00:01 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-05-05, 10:58:59 Critical (3) Resetting the cable modem due to docsDevResetNow
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-05-01, 22:49:55 Critical (3) Resetting the cable modem due to docsDevResetNow
2020-04-30, 11:57:38 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
2020-04-29, 11:17:24 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
2020-04-28, 10:27:19 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-ou;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-04-27, 09:34:32 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2020-03-02, 09:09:45 Critical (3) Telnet user logged out.


Here is my cable connection info from the modem too:

 

<tabindex=-1>Startup Procedure</tabindex=-1>
Procedure Status Comment
Acquire Downstream Channel 597000000 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</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 36 597000000 Hz 1.6 dBmV 43.4 dB 112467335 0 0
2 Locked QAM256 8 423000000 Hz -0.3 dBmV 43.2 dB 111475944 0 0
3 Locked QAM256 9 435000000 Hz 0.4 dBmV 43.4 dB 111479502 0 0
4 Locked QAM256 10 441000000 Hz 0.2 dBmV 43.4 dB 111470522 0 0
5 Locked QAM256 11 447000000 Hz 0.3 dBmV 43.4 dB 111487003 0 0
6 Locked QAM256 12 453000000 Hz 0.6 dBmV 43.6 dB 111490758 0 0
7 Locked QAM256 13 459000000 Hz 0.6 dBmV 43.4 dB 111494427 0 0
8 Locked QAM256 14 465000000 Hz 0.9 dBmV 43.6 dB 111499042 0 0
9 Locked QAM256 15 471000000 Hz 0.9 dBmV 43.6 dB 111502516 0 0
10 Locked QAM256 16 477000000 Hz 0.9 dBmV 43.6 dB 111506806 0 0
11 Locked QAM256 17 483000000 Hz 0.8 dBmV 43.5 dB 111510995 0 0
12 Locked QAM256 18 489000000 Hz 0.7 dBmV 43.5 dB 111513651 0 0
13 Locked QAM256 19 495000000 Hz 0.3 dBmV 41.8 dB 111518055 0 0
14 Locked QAM256 20 501000000 Hz -0.7 dBmV 42.8 dB 111521820 0 0
15 Locked QAM256 21 507000000 Hz -0.9 dBmV 42.9 dB 111525236 0 0
16 Locked QAM256 22 513000000 Hz -0.2 dBmV 42.5 dB 111528979 0 0
17 Locked QAM256 23 519000000 Hz 0.1 dBmV 43.2 dB 111533110 0 0
18 Locked QAM256 24 525000000 Hz 0.0 dBmV 43.3 dB 111537004 0 0
19 Locked QAM256 25 531000000 Hz 0.3 dBmV 41.8 dB 111540829 0 0
20 Locked QAM256 26 537000000 Hz 0.7 dBmV 39.1 dB 111544628 0 0
21 Locked QAM256 27 543000000 Hz 0.7 dBmV 41.6 dB 111548550 0 0
22 Locked QAM256 28 549000000 Hz 0.6 dBmV 43.4 dB 111552160 0 0
23 Locked QAM256 29 555000000 Hz 0.9 dBmV 43.5 dB 111555919 0 0
24 Locked QAM256 30 561000000 Hz 1.1 dBmV 42.7 dB 111559043 0 0
25 Locked QAM256 31 567000000 Hz 1.3 dBmV 41.9 dB 111563481 0 0
26 Locked QAM256 32 573000000 Hz 1.5 dBmV 42.4 dB 111567404 0 0
27 Locked QAM256 33 579000000 Hz 1.6 dBmV 42.6 dB 111570724 0 0
28 Locked QAM256 34 585000000 Hz 1.5 dBmV 43.3 dB 111573888 0 0
29 Locked QAM256 35 591000000 Hz 1.3 dBmV 43.3 dB 111578415 0 0
30 Locked QAM256 37 603000000 Hz 1.6 dBmV 42.3 dB 111594054 0 0
31 Locked QAM256 38 609000000 Hz 1.3 dBmV 42.5 dB 111579381 0 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 73 37800000 Hz 42.0 dBmV
2 Locked ATDMA 74 31400000 Hz 42.5 dBmV
3 Locked ATDMA 75 25000000 Hz 41.8 dBmV
4 Locked ATDMA 76 18600000 Hz 41.5 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</tabindex=-1>
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, 3 48 690000000 Hz 1.5 dBmV 40.3 dB 1108 ~ 2987 12820408 7804635 0
2 Not Locked 0 0 0 Hz -2.1 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels</tabindex=-1>
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

 

All of these values look okay to me, but I am by no means an expert. I am not really sure where to start troubleshooting this either. Any help would be appreciated.

 

I would like to note rebooting the modem usually returns expected speeds for up to ~24hrs.

 

Thanks in advance!