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abedrabbo
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Saturday, November 26th, 2022 11:21 PM

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Arris SB8200 Drops DOCSIS 3.1

I have been running my own Arris SB8200 for a couple of years now, with no issues. Recently, I noticed that after I restart the modem, the download starts off in DOCSIS 3.1 (blue light), but switches back to DOCSIS 3.0 (green light) after a few minutes. After a couple of calls with Xfinity tech, who were very nice, I was told there's nothing they can about it, because they can not diagnose my modem, since it's not Xfinity. That's a bit weak if you ask me! I have tried to restart the modem, reset to factory settings, and the same. Blue for a few minutes, then back to green. To add insult to injury, I received an email saying that my download speed was upped to 400mbps from 300mbps and guess what, I used to get over 300 before this "upgrade" and now I'm lucky if I hit 200mbps. All being equal, nothing has changed. Same modem, same Airport Extreme router, same cables and connections. Any help would be appreciated. 

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3 years ago

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EG

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3 years ago

The concern is not "Community Center" help related. Thread moved here to the proper help section for assistance. 

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abedrabbo

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@EG​ Thank you! I'm a newb to the forums :)

3 years ago

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EG

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@abedrabbo 

No worries !

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? Please mark an Accepted Answer!tick

3 years ago

Andyr1

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3 years ago

Can you post your signal levels and Event Log? It's possible the OFDM, which is typically at the highest frequencies, may be a bit too weak or noisy so it decided to drop it.

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abedrabbo

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@andyross​ 

Connection

The status listed show the connection state of the cable modem. They are used by your service provider to evaluate the operation of the cable modem.

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 507000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK
Security Enabled BPI+
DOCSIS Network Access Enabled Allowed

Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
1 Locked QAM256 507000000 Hz 14.1 dBmV 37.8 dB 245557 0
2 Locked QAM256 513000000 Hz 14.5 dBmV 38.1 dB 179095 0
3 Locked QAM256 519000000 Hz 15.0 dBmV 38.2 dB 114746 0
4 Locked QAM256 525000000 Hz 15.0 dBmV 38.3 dB 110322 0
5 Locked QAM256 531000000 Hz 15.5 dBmV 38.6 dB 76437 0
6 Locked QAM256 537000000 Hz 16.0 dBmV 38.8 dB 54112 0
7 Locked QAM256 543000000 Hz 15.8 dBmV 38.7 dB 65994 0
8 Locked QAM256 549000000 Hz 16.3 dBmV 38.9 dB 40981 0
9 Locked QAM256 555000000 Hz 16.8 dBmV 39.2 dB 25526 0
10 Locked QAM256 561000000 Hz 17.0 dBmV 39.4 dB 22595 0
11 Locked QAM256 567000000 Hz 17.0 dBmV 39.3 dB 26009 0
12 Locked QAM256 573000000 Hz 17.2 dBmV 39.5 dB 25814 0
13 Locked QAM256 579000000 Hz 16.8 dBmV 39.1 dB 40426 0
14 Locked QAM256 585000000 Hz 17.2 dBmV 39.4 dB 31182 0
15 Locked QAM256 591000000 Hz 17.3 dBmV 39.6 dB 33622 0
16 Locked QAM256 597000000 Hz 17.8 dBmV 39.6 dB 23643 0
17 Locked QAM256 603000000 Hz 17.5 dBmV 39.5 dB 32441 0
18 Locked QAM256 609000000 Hz 17.9 dBmV 39.7 dB 23281 0
19 Locked QAM256 615000000 Hz 18.0 dBmV 39.7 dB 20608 0
20 Locked QAM256 621000000 Hz 18.5 dBmV 40.1 dB 12658 0
21 Locked QAM256 627000000 Hz 18.7 dBmV 39.6 dB 13596 0
22 Locked QAM256 633000000 Hz 19.1 dBmV 39.9 dB 8801 0
23 Locked QAM256 639000000 Hz 18.6 dBmV 39.9 dB 14873 0
24 Locked QAM256 645000000 Hz 19.4 dBmV 40.5 dB 6284 0
25 Locked Other 780000000 Hz 22.6 dBmV 39.0 dB 740694548 0
26 Not Locked QAM256 0 Hz 0.0 dBmV 40.6 dB 4974 0
27 Locked QAM256 651000000 Hz 19.6 dBmV 40.8 dB 4591 0
28 Locked QAM256 657000000 Hz 19.6 dBmV 40.5 dB 5012 0
29 Locked QAM256 663000000 Hz 19.7 dBmV 40.9 dB 3438 0
30 Locked QAM256 669000000 Hz 20.1 dBmV 40.3 dB 4609 4
31 Locked QAM256 675000000 Hz 19.8 dBmV 40.6 dB 4886 0
32 Locked QAM256 681000000 Hz 19.6 dBmV 40.4 dB 8302 46



Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 53 Locked SC-QAM Upstream 16400000 Hz 6400000 Hz 39.0 dBmV
2 54 Locked SC-QAM Upstream 22800000 Hz 6400000 Hz 39.0 dBmV
3 55 Locked SC-QAM Upstream 29200000 Hz 6400000 Hz 39.0 dBmV
4 56 Locked SC-QAM Upstream 35600000 Hz 6400000 Hz 39.0 dBmV



Current System Time: Sun Nov 27 12:37:03 2022

3 years ago

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abedrabbo

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@andyross​ Event log with redacted Mac addresses as requested. 

Event Log

The table below contains the log of events that the SB8200 has detected. This log can be important to the service provider to help diagnose and correct problems, if any should occur.

Date Time Event ID Event Level Description
11/27/2022 11:05 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 11:05 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 10:05 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 10:04 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 09:11 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 09:10 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 08:17 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 08:16 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 05:35 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 05:34 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 04:41 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 04:40 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 03:47 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 03:46 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 03:45 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 03:45 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 02:53 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 02:52 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 01:55 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 01:55 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 01:05 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 01:04 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 00:05 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/27/2022 00:05 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 22:23 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 22:22 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 22:15 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xxCMTS-MAC=x;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 22:15 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 21:29 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 21:28 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 20:26 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 20:26 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 20:25 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 20:25 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 18:35 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 18:35 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 17:53 74010100 6 "CM-STATUS message sent. Event Type Code: 22; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 17:52 74010100 6 "CM-STATUS message sent. Event Type Code: 20; Chan ID: 25; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 17:05 84000500 3 "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
11/26/2022 17:05 67061600 6 "DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 2436694066 6 "Honoring MDD; IP provisioning mode = IPv6"
01/01/1970 00:01 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.1;"

(edited)

3 years ago

0

EG

Expert

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111.4K Messages

3 years ago

@abedrabbo 

Please redact all of the CM MAC and the CMTS MAC addresses in your error log entries for your privacy. They are considered to be personal information. The posting of personally identifiable information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically. It flagged your post as "Private".

4

abedrabbo

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@EG​ Roger that! I've redacted Mac addresses. 

3 years ago

0

EG

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111.4K Messages

@abedrabbo​ 

Is there a drop amplifier in the coax cable line leading to the modem ? If so, try bypassing it and see.

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? Please mark an Accepted Answer!tick

3 years ago

abedrabbo

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@EG​ There's no amplifier in my unit, I used to have a splitter, but got rid of that a long time ago and connect directly to the wall. Having said that I remember Comcast adding amplifiers to our building.

3 years ago

0

EG

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111.4K Messages

@abedrabbo​ 

Ok. I saw that you posted about getting a tech visit. Good luck with it ! Please post back here in your topic with how things turn out.

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? Please mark an Accepted Answer!tick

3 years ago

0

Jim721

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3.5K Messages

3 years ago

Your downstream signals are way to high and out of spec. You need a tech out. 

1

abedrabbo

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@Jim721​ Thank you. What could cause this? Old building with old coax cables? 

3 years ago

0

Jim721

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3.5K Messages

3 years ago

Generally when you have old coax or bad fittings or splitters your DS signals will drop. That said your levels are way to high that tells me something outside of your house needs adjusted or fixed like possibly an amplifier. Also your Upstream levels are on the low side of ok. That makes me think your coax cables and connections are likely good. If not your upstream signals would be spiked. Just my 2 cents after years of dealing with cable internet. I do not work for comcast. 

(edited)

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abedrabbo

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@Jim721​ I really appreciate it. I think Comcast has installed a bunch of amplifiers in our building because of its age. I will call next week and ask for a tech to come out.

3 years ago

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