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High Upstream Channel Power and T3/T4 time outs

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Regular Visitor

High Upstream Channel Power and T3/T4 time outs

Hi maybe someone can help me, over the past year I'm having increasing T3/T4 time outs with loss of connection 5-10 times a day.  I spent hours on chat with Xfinity and they told me to connect the modem directly to the drop coaxial cable - which works and decreases the errors, and also reduces the modem upstream power from 51-59 with splitter to around 47 without.  They spent most of the time trying to up sell me on renting their gear and adding more TV I don't need.  The 3 way splitter connected my modem and 2 TV's, now to watch TV I have to go outside and attach the splitter, which I think is a ridiculous solution.  I also tried only connecting one TV to the splitter and it was better but still too frequent T3 errors, and upstream power above 50.  The photos are from after disconnecting splitter so you can see the upstream power decreased to 47, the error logs show the time outs prior to disconnecting the splitter.  Thanks for any help, I'm strongly considering switching to RCN.  Also the modem is Netgear cm1000 (recommended by comcast) and I also have a  Netgear Nighthawk router.011A4A1A-4A70-4119-9D8D-705D08A9722A.jpeg18657AF2-3F58-44DF-8766-D0E534503001.jpeg09D71E4A-A020-4535-ADA4-F23CCF5A6AFD.jpeg

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Regular Visitor

Re: High Upstream Channel Power and T3/T4 time outs

Pic's:

 

C0986FE0-00CF-44D1-A4FB-561E7240B071.jpeg724EC647-5B60-4F2A-9F33-C351AD7ECB5C.jpegAE251924-772C-4780-BC1D-C93B7F4D3794.jpeg

Expert

Re: High Upstream Channel Power and T3/T4 time outs

Can't see your pics. Since you are a new poster, they need to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting them at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to them here.

Or copy all of the text of the status page and paste it into the body of your next post here.



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Regular Visitor

Re: High Upstream Channel Power and T3/T4 time outs

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</tabindex=-1>
Procedure Status Comment
Acquire Downstream Channel 555000000 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 13 555000000 Hz -1.6 dBmV 40.3 dB 3311821338 5769 7339
2 Locked QAM256 1 477000000 Hz -0.7 dBmV 41.1 dB 3345784595 8596 13966
3 Locked QAM256 2 483000000 Hz -0.8 dBmV 41.2 dB 3345783100 7494 13402
4 Locked QAM256 3 489000000 Hz -0.8 dBmV 41.1 dB 3345780009 7900 13739
5 Locked QAM256 4 495000000 Hz -0.9 dBmV 40.9 dB 3325791664 6355 9292
6 Locked QAM256 5 507000000 Hz -1.1 dBmV 40.8 dB 3345516929 6968 13181
7 Locked QAM256 6 513000000 Hz -1.1 dBmV 40.5 dB 3345509306 6871 13162
8 Locked QAM256 7 519000000 Hz -1.2 dBmV 40.8 dB 3345518234 6538 12225
9 Locked QAM256 8 525000000 Hz -1.1 dBmV 40.7 dB 3325862703 6226 8077
10 Locked QAM256 9 531000000 Hz -1.2 dBmV 40.6 dB 3345551186 6298 12399
11 Locked QAM256 10 537000000 Hz -1.2 dBmV 40.6 dB 3345553562 6325 12217
12 Locked QAM256 11 543000000 Hz -1.5 dBmV 40.4 dB 3345553150 7012 14851
13 Locked QAM256 12 549000000 Hz -1.6 dBmV 40.5 dB 3345831470 7041 11289
14 Locked QAM256 14 561000000 Hz -1.6 dBmV 40.2 dB 3345837860 7078 11498
15 Locked QAM256 15 567000000 Hz -1.6 dBmV 40.2 dB 3325939755 5635 8446
16 Locked QAM256 16 573000000 Hz -1.9 dBmV 40.3 dB 3345831999 12996 17768
17 Locked QAM256 17 579000000 Hz -1.9 dBmV 40.1 dB 3345905475 6772 10771
18 Locked QAM256 18 585000000 Hz -2.0 dBmV 40.0 dB 3345629569 7794 18224
19 Locked QAM256 19 591000000 Hz -2.1 dBmV 39.9 dB 3345633805 6444 11523
20 Locked QAM256 20 597000000 Hz -2.1 dBmV 39.8 dB 3345650506 14320 24398
21 Locked QAM256 21 603000000 Hz -2.2 dBmV 39.6 dB 3326065593 5271 6897
22 Locked QAM256 22 609000000 Hz -2.3 dBmV 39.5 dB 3345910398 6925 9475
23 Locked QAM256 23 615000000 Hz -2.4 dBmV 39.6 dB 3345913845 6939 8868
24 Locked QAM256 34 453000000 Hz -0.9 dBmV 41.1 dB 3345887191 8736 15738
25 Locked QAM256 35 459000000 Hz -1.0 dBmV 41.0 dB 3345892124 8798 14600
26 Locked QAM256 36 465000000 Hz -0.9 dBmV 40.9 dB 3345896024 8394 14721
27 Locked QAM256 37 471000000 Hz -0.8 dBmV 41.0 dB 3345898281 8131 13849
28 Locked QAM256 38 429000000 Hz -0.9 dBmV 41.4 dB 3345894561 10738 16333
29 Locked QAM256 39 435000000 Hz -0.9 dBmV 41.3 dB 3345897085 10269 16424
30 Locked QAM256 40 441000000 Hz -0.9 dBmV 41.1 dB 3345902179 10039 16278
31 Locked QAM256 41 447000000 Hz -0.9 dBmV 41.3 dB 3345905535 9394 15641
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 81 35800000 Hz 46.8 dBmV
2 Locked ATDMA 82 29400000 Hz 46.8 dBmV
3 Locked ATDMA 83 23000000 Hz 47.0 dBmV
4 Locked ATDMA 84 16600000 Hz 47.8 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</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 33 722000000 Hz -2.2 dBmV 37.3 dB 1228 ~ 2867 638474026 569686084 770
2 Not Locked 0 0 0 Hz 1.1 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
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Regular Visitor

Re: High Upstream Channel Power and T3/T4 time outs

 
 
 
 
Time Priority Description
2020-06-07, 13:38:53 Warning (5) Dynamic Range Window violation
2020-06-07, 13:38:53 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 12:26:19 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:39:17 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0 1 2 3.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:39:11 Notice (6) CM-STATUS message sent. Event Type Code: 23; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:39:11 Notice (6) CM-STATUS message sent. Event Type Code: 22; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:38:45 Warning (5) Dynamic Range Window violation
2020-06-07, 11:38:45 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:38:07 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:38:07 Warning (5) MDD message timeout;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:38:02 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:38:01 Warning (5) MDD message timeout;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:37:58 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:37:55 Warning (5) MDD message timeout;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:37:54 Notice (6) CM-STATUS message sent. Event Type Code: 2; Chan ID: 4 5 6 7 8 9 10 11 18 19 20; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:37:53 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:19:35 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:19:12 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:10:07 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:09:36 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 11:08:31 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 10:00:05 Notice (6) CM-STATUS message sent. Event Type Code: 8; Chan ID: 82 83 84; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:59:35 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:59:25 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 83 84; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:59:18 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:59:17 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 0;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:59:17 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:59:17 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:59:17 Notice (6) CM-STATUS message sent. Event Type Code: 7; Chan ID: 83; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:59:00 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:58:58 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:58:58 Critical (3) Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
2020-06-07, 09:57:51 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:b9:8a:ae:a4:38;CMTS-MAC=00:01:5c:6f:5c:5a;CM-QOS=1.1;CM-VER=3.1;
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Regular Visitor

Re: High Upstream Channel Power and T3/T4 time outs

Thanks, after removing the splitter I think there was only the two warnings at the top of the event log "Dynamic Range Window Violation"  Most of the other one's with splitter in place were T3 and T4 warnings.