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Intermitent slow/no download speeds

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Intermitent slow/no download speeds

I need help diagnosing slow/no download speeds.  For the last week have been experiencing intermitent slowdowns to 0 Mbps that have gotten increasingly more frequent.  Normal speed is ~150 Mbps.  Using a Netgear CM100 Dcois 3.1 modem.  Rebooting does not help.  Connecting direct to the modem does not help. Upload speeds remain consistent at 10 Mbps even when the download speed drops to 0 (all speed measurements using the Xfinity speedtest).

 

Last week troubleshooted with Xfinity support, couldn't find anything.  Had a tech come out and she replaced the wiring between the modem and the entry point.  Still having same intermitant slow downs.

 

Right now getting about 40 Mbps.  Here is a cut/paste of the modem error messages and connection stats  Would appreciate any suggestions of what to try next.  Thanks!!!!

 

Time Priority Description
2019-02-23, 08:57:38 Notice (6) CM-STATUS message sent. Event Type Code: 4; Chan ID: 24 31 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:57:10 Warning (5) MDD message timeout;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:57:00 Notice (6) CM-STATUS message sent. Event Type Code: 4; Chan ID: 24 31 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:56:36 Warning (5) MDD message timeout;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:56:30 Notice (6) CM-STATUS message sent. Event Type Code: 4; Chan ID: 24 31 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:56:02 Warning (5) MDD message timeout;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:55:26 Notice (6) CM-STATUS message sent. Event Type Code: 4; Chan ID: 24 31 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:55:20 Warning (5) MDD message timeout;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:54:50 Notice (6) CM-STATUS message sent. Event Type Code: 4; Chan ID: 24 31 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:54:18 Warning (5) MDD message timeout;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:54:13 Notice (6) CM-STATUS message sent. Event Type Code: 4; Chan ID: 24 31 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:54:04 Warning (5) MDD message timeout;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:51:51 Notice (6) CM-STATUS message sent. Event Type Code: 4; Chan ID: 24 31 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:51:42 Warning (5) MDD message timeout;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 08:51:10 Notice (6)

CM-STATUS message sent. Event Type Code: 4; Chan ID: 24 31 ; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:fd:6a:c8;CMTS-MAC=00:01:5c:99:f8:57;CM-QOS=1.1;CM-VER=3.1;

 

 

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 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 (Partial Service)</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 18 573000000 Hz -17.7 dBmV 32.7 dB 36241380 2 0
2 Locked QAM256 1 465000000 Hz -4.4 dBmV 41.7 dB 34864621 0 0
3 Locked QAM256 2 471000000 Hz -5.4 dBmV 41.4 dB 34868579 0 0
4 Locked QAM256 3 477000000 Hz -5.8 dBmV 41.4 dB 34870896 0 0
5 Locked QAM256 4 483000000 Hz -6.2 dBmV 41.2 dB 34876607 0 0
6 Locked QAM256 5 489000000 Hz -8.5 dBmV 39.9 dB 34880418 0 0
7 Locked QAM256 6 495000000 Hz -10.1 dBmV 39.0 dB 34884390 0 0
8 Locked QAM256 7 501000000 Hz -9.0 dBmV 39.4 dB 34890397 0 0
9 Locked QAM256 8 507000000 Hz -8.4 dBmV 38.9 dB 34895574 0 0
10 Locked QAM256 9 513000000 Hz -8.9 dBmV 39.5 dB 34899417 0 0
11 Locked QAM256 10 519000000 Hz -10.1 dBmV 38.9 dB 34902614 0 0
12 Locked QAM256 11 525000000 Hz -11.4 dBmV 38.3 dB 34909892 0 0
13 Locked QAM256 12 531000000 Hz -11.2 dBmV 38.4 dB 34917391 0 0
14 Locked QAM256 13 537000000 Hz -12.9 dBmV 36.7 dB 34928021 0 0
15 Locked QAM256 14 543000000 Hz -14.0 dBmV 36.1 dB 34932111 0 0
16 Locked QAM256 15 555000000 Hz -15.6 dBmV 34.1 dB 34943193 0 0
17 Locked QAM256 16 561000000 Hz -16.3 dBmV 34.2 dB 34947548 0 0
18 Locked QAM256 17 567000000 Hz -15.6 dBmV 34.7 dB 34956999 0 0
19 Locked QAM256 19 579000000 Hz -20.4 dBmV 30.4 dB 34962213 50 0
20 Locked QAM256 20 585000000 Hz -19.0 dBmV 31.6 dB 34965763 1 0
21 Locked QAM256 21 591000000 Hz -20.2 dBmV 30.5 dB 34968738 58 0
22 Locked QAM256 22 597000000 Hz -20.7 dBmV 29.9 dB 34962217 405 0
23 Locked QAM256 23 603000000 Hz -22.9 dBmV 27.7 dB 33956752 1007905 22
24 Locked QAM256 24 609000000 Hz -24.4 dBmV 26.6 dB 10673852 22411093 1875280
25 Locked QAM256 26 615000000 Hz -22.1 dBmV 28.5 dB 34874253 75055 0
26 Locked QAM256 27 621000000 Hz -23.7 dBmV 26.7 dB 16118962 18007911 827312
27 Locked QAM256 29 633000000 Hz -23.9 dBmV 26.8 dB 21431945 13374872 151327
28 Locked QAM256 30 639000000 Hz -22.6 dBmV 28.1 dB 34722920 238666 0
29 Locked QAM256 31 645000000 Hz -23.2 dBmV 27.0 dB 13002976 19112079 2842897
30 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0
31 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 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 1 35600000 Hz 36.8 dBmV
2 Locked ATDMA 2 29200000 Hz 36.8 dBmV
3 Locked ATDMA 3 22800000 Hz 36.8 dBmV
4 Locked ATDMA 4 16000000 Hz 36.8 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, 255 25 690000000 Hz -25.4 dBmV 18.8 dB 1108 ~ 2987 69594095 68735252 860608
2 Not Locked 0, 255 0 0 Hz -3.5 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

Current System Time: Sat Feb 23 08:59:23 2019 

 

Highlighted
Expert

Re: Intermitent slow/no download speeds

You have very poor signal levels. Since you've already had a tech out...

 

I've asked an employee to assist you. You should expect a reply in this thread. 

 

FYI: They owe you a $20 credit for every tech visit after the first for the same problem. You can also get a credit for your service from the time you first reported the issue until it is resolved.


I am not a Comcast Employee.
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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Official Employee

Re: Intermitent slow/no download speeds

Hello, torr99. Thanks for reaching out to us on the forums. I apologize to hear you are having issues with the internet speed especially after a tech has been out there to look into the issue. I would like to look into this further. Can you please send me a PM with your first and last name so I may further assist you?


I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: CARE, Product, Leadership. We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!
New Poster

Re: Intermitent slow/no download speeds

Tech came out and reworked the connections from the house out to the pole.  All looks good now.  Power levels are way higher and speedtest is back at 150 Mbps +.

 

Thanks for all the help!

Expert

Re: Intermitent slow/no download speeds

Excellent news. As the issue is now resolved I'm going to close this thread. Thank you for visiting the Xfinity Support Forums and feel free to post a new thread should another issue arise. 


I am not a Comcast Employee.
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.
Was your question answered? Mark the post as Best Answer!
Official Employee

Re: Intermitent slow/no download speeds

I'm glad I was able to assist you, torr99. If you ever need further assistance don't hesitate to reach out to us.


I am an Official Comcast Employee.
Official Employees are from multiple teams within Comcast: CARE, Product, Leadership. We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!