Visitor
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2 Messages
Motorola MB8611 Modem Intermittent Connectivity
Hi All,
I recently purchased a Motorola MB8611 modem, which is rated for 2.5 gbps and I was able to set things up with my 1gbps Xfinity internet plan. However, I'm experiencing frequent intermittent connectivity issues where all devices on my network (wired and wireless) lose connection for at least a 2-3 minutes at a time.
When i upgraded my internet plan to the 1 gbps plan a couple weeks ago, I switched over from a Motorola 7621 modem to the new one (MB8611) to take advantage of the faster download speeds that come with my plan. The MB8611 is a DOCSIS 3.1 modem and is certified to work with Xfinity. Unfortunately, my internet intermittent connectivity issues began when I switched to the new modem.
Any advice and support is greatly appreciated as I haven't had any success by restarting the modem, going through the automated Xfinity troubleshooting support, etc.
Here's the info from the modem when I access it from 192.168.100.1:
Software
Device Information
Cable Specification Version |
DOCSIS 3.1 |
Hardware Version |
V1.0 |
Software Version |
8611-19.2.20 |
Cable Modem MAC Address |
REDACTED |
Cable Modem Serial Number |
REDACTED |
CM Certificate |
Installed |
|
Prod_19.2_d31 |
Connection
Downstream Bonded Channels
Channel |
Lock Status |
Modulation |
Channel ID |
Freq. (MHz) |
Pwr (dBmV) |
SNR (dB) |
Corrected |
Uncorrected |
1 |
Locked |
QAM256 |
41 |
693.0 |
4.1 |
41.5 |
0 |
0 |
2 |
Locked |
QAM256 |
14 |
531.0 |
4.9 |
42.1 |
0 |
0 |
3 |
Locked |
QAM256 |
15 |
537.0 |
4.6 |
42.0 |
0 |
0 |
4 |
Locked |
QAM256 |
16 |
543.0 |
4.8 |
42.1 |
0 |
0 |
5 |
Locked |
QAM256 |
17 |
549.0 |
5.2 |
42.1 |
0 |
0 |
6 |
Locked |
QAM256 |
18 |
555.0 |
5.3 |
42.0 |
0 |
0 |
7 |
Locked |
QAM256 |
19 |
561.0 |
5.0 |
42.1 |
0 |
0 |
8 |
Locked |
QAM256 |
20 |
567.0 |
5.1 |
41.9 |
0 |
0 |
9 |
Locked |
QAM256 |
21 |
573.0 |
5.5 |
42.1 |
0 |
0 |
10 |
Locked |
QAM256 |
22 |
579.0 |
5.2 |
41.8 |
0 |
0 |
11 |
Locked |
QAM256 |
23 |
585.0 |
4.9 |
41.8 |
0 |
0 |
12 |
Locked |
QAM256 |
24 |
591.0 |
5.4 |
41.9 |
0 |
0 |
13 |
Locked |
QAM256 |
25 |
597.0 |
5.6 |
41.9 |
0 |
0 |
14 |
Locked |
QAM256 |
26 |
603.0 |
5.2 |
41.8 |
0 |
0 |
15 |
Locked |
QAM256 |
27 |
609.0 |
4.9 |
41.6 |
0 |
0 |
16 |
Locked |
QAM256 |
28 |
615.0 |
5.2 |
41.8 |
0 |
0 |
17 |
Locked |
QAM256 |
29 |
621.0 |
5.4 |
41.7 |
0 |
0 |
18 |
Locked |
QAM256 |
30 |
627.0 |
5.1 |
41.6 |
0 |
0 |
19 |
Locked |
QAM256 |
31 |
633.0 |
5.2 |
41.6 |
0 |
0 |
20 |
Locked |
QAM256 |
32 |
639.0 |
5.3 |
41.4 |
0 |
0 |
21 |
Locked |
QAM256 |
33 |
645.0 |
5.1 |
41.5 |
0 |
0 |
22 |
Locked |
QAM256 |
34 |
651.0 |
4.9 |
41.4 |
0 |
0 |
23 |
Locked |
QAM256 |
35 |
657.0 |
5.0 |
41.4 |
0 |
0 |
24 |
Locked |
QAM256 |
36 |
663.0 |
5.2 |
41.8 |
0 |
0 |
25 |
Locked |
QAM256 |
37 |
669.0 |
5.0 |
41.8 |
0 |
0 |
26 |
Locked |
QAM256 |
38 |
675.0 |
4.8 |
41.4 |
4 |
0 |
27 |
Locked |
QAM256 |
39 |
681.0 |
4.7 |
41.7 |
0 |
0 |
28 |
Locked |
QAM256 |
40 |
687.0 |
4.5 |
41.7 |
0 |
0 |
29 |
Locked |
QAM256 |
42 |
699.0 |
4.1 |
41.7 |
0 |
0 |
30 |
Locked |
QAM256 |
43 |
705.0 |
4.2 |
41.7 |
0 |
0 |
31 |
Locked |
QAM256 |
44 |
711.0 |
3.9 |
41.4 |
0 |
0 |
32 |
Locked |
OFDM PLC |
45 |
762.0 |
4.8 |
41.4 |
54955581 |
0 |
Upstream Bonded Channels
Channel |
Lock Status |
Channel Type |
Channel ID |
Symb. Rate (Ksym/sec) |
Freq. (MHz) |
Pwr (dBmV) |
1 |
Locked |
SC-QAM |
1 |
5120 |
35.6 |
39.8 |
2 |
Locked |
SC-QAM |
2 |
5120 |
29.2 |
40.0 |
3 |
Locked |
SC-QAM |
3 |
5120 |
22.8 |
39.8 |
4 |
Locked |
SC-QAM |
4 |
5120 |
16.4 |
40.3 |
5 |
Locked |
SC-QAM |
5 |
2560 |
40.4 |
38.3 |
Event Log
Time |
Priority |
Description |
Time Not Established |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
No Ranging Response received - T3 time-out;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
No Ranging Response received - T3 time-out;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
No Ranging Response received - T3 time-out;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
No Ranging Response received - T3 time-out;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
No Ranging Response received - T3 time-out;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
No Ranging Response received - T3 time-out;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
No Ranging Response received - T3 time-out;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Critical (3) |
No Ranging Response received - T3 time-out;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Time Not Established |
Notice (6) |
Honoring MDD; IP provisioning mode = IPv6 |
07:27:32 |
Notice (6) |
DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
07:27:55 |
Notice (6) |
CM-STATUS message sent. Event Type Code: 24; Chan ID: 45; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0.;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.1; |
Accepted Solution
BruceW
Gold Problem Solver
•
26.4K Messages
2 years ago
The signal stats you posted all look good, but there are other stats that the modem does not report, and the event log indicates that the modem is having trouble communicating with Comcast.
Network connection problems like this are often due to poor coax connections or damaged coax cable, usually in or near your home. Running the cable through a surge protector, a defective splitter, or too many splitters can cause signal problems as well. If there is an amplifier in the line make sure it's getting power.
If you want to troubleshoot this yourself, please see Internet Troubleshooting Tips. If you can't find the problem or you'd rather have Comcast take care of it, call them at the phone number on your bill or 1-800-Comcast, or use one of the options on https://www.xfinity.com/support/contact-us/. It's not likely they can fix the problem remotely. If not, insist they send a tech out to identify the cause and correct it.
If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit ($70-$100) unless you have their Service Protection Plan ( https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device or anything outside your home you shouldn't be charged.
Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post by scrolling down to "Comment on this post here...", I am notified of your response. But if you select Reply, I am NOT notified and may not be aware of your response.
0
Jlavaseur
Problem Solver
•
948 Messages
2 years ago
I have the mb8611, it performs flawlessly for me, I ran across this article, it may or may not help you, but good reading non the less..
https://www.smallnetbuilder.com/wireless/wireless-features/wi-fi-ping-spikes-causes-and-fixes/
(edited)
0
XfinityRay
Official Employee
•
2.8K Messages
2 years ago
Greetings, @user_1bf73c. I see there is a lot of great help in this thread already! Have you had time to look at the article @Jlavaseur posted or gone over any of the possible troubleshooting steps that @EG provided?
0
user_1bf73c
Visitor
•
2 Messages
2 years ago
Hi All,
Thanks for the quick responses and helpful feedback!
I was able to connect my modem to the main coax service line coming into the house (Upstream of a powered coax splitter) and so far so good. It's looking like the coax splitter or perhaps the coax cable i was using may have been the culprit.
The only headscratcher for me is that my older Motorola 7621 modem worked fine downstream of the coax splitter and using the same coax cable.
1
wtfovertime
New Poster
•
6 Messages
2 years ago
This is still an issue
0
0
EG
Expert
•
110.3K Messages
2 years ago
@wtfovertime
Are you the original poster ?
0
0