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High Latency and Packet Loss - Menlo Park

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Regular Visitor

High Latency and Packet Loss - Menlo Park

All,

Wondering if other Menlo Park (94025) customers are seeing this:  I get extremely high latency, beginning about 9am and lasting until about 5p (gee, working hours?).  My pings to 8.8.8.8 are in the 1500-3000ms range.  Obviously, Comcast is denying any issues but my ping values to both my router (Ubiquiti) and Cable Modem (Netgear CM1150v) are in the 1-2ms range.

 

This first appeared when S-I-P started in March but went away until about 10 days ago.  Now, for all work related purposes (e.g., Zoom or Teams), my Internet is effectively useless.


I am paying for Gigabit Internet and getting inconsistent download speeds:  sometimes as high as 850Mb/s but often 250-300 Mb/s but even as lowas 3-5Mb/s.  I was on a remote desktop with Netgear and the reviewed my modem and all is well.

 

Help?

Thanks,
John

 

 
 
 
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
 
Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 525000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)
 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 20 525000000 Hz 1.7 dBmV 39.2 dB 7351 29
2 Locked QAM256 17 507000000 Hz 1.9 dBmV 39.4 dB 6578 20
3 Locked QAM256 18 513000000 Hz 1.8 dBmV 39.4 dB 6534 31
4 Locked QAM256 19 519000000 Hz 1.8 dBmV 39.3 dB 7206 42
5 Locked QAM256 21 531000000 Hz 1.8 dBmV 39.2 dB 7857 18
6 Locked QAM256 22 537000000 Hz 1.9 dBmV 39.1 dB 7915 11
7 Locked QAM256 23 543000000 Hz 1.8 dBmV 39 dB 8484 9
8 Locked QAM256 24 549000000 Hz 2.1 dBmV 39.1 dB 7555 14
9 Locked QAM256 25 555000000 Hz 2.2 dBmV 38.9 dB 8188 10
10 Locked QAM256 26 561000000 Hz 2.4 dBmV 39 dB 8286 29
11 Locked QAM256 27 567000000 Hz 2.6 dBmV 38.9 dB 8550 17
12 Locked QAM256 28 573000000 Hz 2.6 dBmV 38.9 dB 9594 18
13 Locked QAM256 29 579000000 Hz 2.6 dBmV 38.7 dB 11417 8
14 Locked QAM256 30 585000000 Hz 2.6 dBmV 38.6 dB 11924 19
15 Locked QAM256 31 591000000 Hz 2.8 dBmV 38.7 dB 10749 11
16 Locked QAM256 32 597000000 Hz 3.1 dBmV 38.7 dB 9629 17
17 Locked QAM256 33 603000000 Hz 3.2 dBmV 38.6 dB 10770 22
18 Locked QAM256 34 609000000 Hz 3.3 dBmV 38.6 dB 11427 3
19 Locked QAM256 35 615000000 Hz 3.5 dBmV 38.6 dB 11609 14
20 Locked QAM256 36 621000000 Hz 3.7 dBmV 38.5 dB 11767 4
21 Locked QAM256 37 627000000 Hz 3.9 dBmV 38.5 dB 11798 8
22 Locked QAM256 38 633000000 Hz 3.9 dBmV 38.4 dB 12763 3
23 Locked QAM256 39 639000000 Hz 4.1 dBmV 38.4 dB 10999 2
24 Locked QAM256 40 645000000 Hz 4 dBmV 38.4 dB 11644 8
25 Locked QAM256 41 651000000 Hz 4 dBmV 38.3 dB 12129 4
26 Locked QAM256 42 657000000 Hz 4 dBmV 38.3 dB 11386 10
27 Locked QAM256 43 663000000 Hz 4.1 dBmV 38.3 dB 11505 9
28 Locked QAM256 44 669000000 Hz 4.2 dBmV 38.3 dB 11122 0
29 Locked QAM256 45 675000000 Hz 4.1 dBmV 38 dB 12314 9
30 Locked QAM256 46 681000000 Hz 4 dBmV 38.2 dB 12519 0
31 Locked QAM256 47 687000000 Hz 4.4 dBmV 38.3 dB 10353 1
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 17300000 Hz 48.5 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 23700000 Hz 49 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 30300000 Hz 49.5 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 36700000 Hz 49 dBmV
5 Locked ATDMA 5 1280 Ksym/sec 41200000 Hz 50.3 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
Downstream OFDM Channels
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 850000000 Hz 4.5 dBmV 37.2 dB 1108 ~ 2987 1771375376 712646654 0
2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0
 
Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked 0 0 0 Hz 0 dBmV
2 Not Locked 0 0 0 Hz 0 dBmV
 
Highlighted
Expert

Re: High Latency and Packet Loss - Menlo Park

The upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Regular Visitor

Re: High Latency and Packet Loss - Menlo Park

Thanks kindly for your response.  I current have a single splitter (it's a 1 in 4 out but only 2 outs are used:  cable modem and to TV box).  It is supposedly high quality, a digital splitter by Evoluation 5-1002 MHz.  Frustrating and Comcast won't roll anyone until COVID is over.

Highlighted
Expert

Re: High Latency and Packet Loss - Menlo Park

Reduce that splitter down to being a 2-way splitter if you don't need that many ports. It has less signal loss.



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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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Highlighted
Regular Visitor

Re: High Latency and Packet Loss - Menlo Park

Ok, I'll give a try.  All I have lying around is an older Monster Cable 2G splitter, one of the "gold" ones you advise against.  Waste of time?

Highlighted
Expert

Re: High Latency and Packet Loss - Menlo Park

Here are some quality brand splitters that Comcast actually uses in different market areas;

Antronix CMC2002H 2-Way Splitter: http://www.amazon.com/Antronix-CMC2002H-2-Way-Splitter/dp/B001E4OH1E

Regal 2 WAY 1 GHZ Splitter: http://www.amazon.com/DIG702867-Regal-WAY-GHZ-SPLITTER/dp/B0018BQMUM/ref=sr_1_2?s=electronics&ie=UTF...

Extreme Broadband BDS102H 2-Way Digital Coax Splitter: http://www.amazon.com/EXTREME-DIGITAL-PERFORMANCE-CABLE-SPLITTER/dp/B007YV0UQW

Holland 2-way horizontal splitter 5-1000 MHz with ground.http://www.3starinc.com/holland_2-way_horizontal_splitter_5-1000_mhz-w-ground.html

Sv-2g 2-way Splitter 5-1000mhz: http://www.amazon.com/Sv-2g-2-way-Splitter-5-1000mhz-Sv2g/dp/B003TH36CK






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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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Highlighted
Regular Visitor

Re: High Latency and Packet Loss - Menlo Park

Thanks, again.  I got the Extreme 1-2 splitter and installed but to no avail.  Got a lot of error messages on my modem this am (before I installed the new splitter):

 

No Maintenance Broadcasts for Ranging opportunities received - T2 time-out

No Ranging Response received - T3 time-out

SYNC Timing Synchronization failure - Loss of Sync

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing

Current cable snapshot:

 

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 525000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)
 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 20 525000000 Hz 5.6 dBmV 38.8 dB 2054 2825
2 Locked QAM256 8 447000000 Hz 4.5 dBmV 39.1 dB 399 0
3 Locked QAM256 9 453000000 Hz 4.7 dBmV 39.1 dB 653 876
4 Locked QAM256 10 459000000 Hz 4.9 dBmV 39.2 dB 603 859
5 Locked QAM256 11 465000000 Hz 5 dBmV 39.1 dB 638 860
6 Locked QAM256 12 471000000 Hz 5 dBmV 39.1 dB 669 853
7 Locked QAM256 13 477000000 Hz 5.2 dBmV 39.2 dB 728 842
8 Locked QAM256 14 483000000 Hz 5.1 dBmV 39.1 dB 752 870
9 Locked QAM256 15 489000000 Hz 5.1 dBmV 39 dB 827 867
10 Locked QAM256 16 495000000 Hz 5.1 dBmV 38.9 dB 1009 852
11 Locked QAM256 17 507000000 Hz 5.5 dBmV 39 dB 944 831
12 Locked QAM256 18 513000000 Hz 5.5 dBmV 38.9 dB 934 850
13 Locked QAM256 19 519000000 Hz 5.5 dBmV 38.9 dB 1155 842
14 Locked QAM256 21 531000000 Hz 5.7 dBmV 38.8 dB 1462 839
15 Locked QAM256 22 537000000 Hz 5.7 dBmV 38.8 dB 1539 849
16 Locked QAM256 23 543000000 Hz 5.7 dBmV 38.6 dB 1773 849
17 Locked QAM256 24 549000000 Hz 5.9 dBmV 38.7 dB 1486 851
18 Locked QAM256 25 555000000 Hz 6 dBmV 38.5 dB 1770 846
19 Locked QAM256 26 561000000 Hz 6.1 dBmV 38.5 dB 1922 849
20 Locked QAM256 27 567000000 Hz 6.3 dBmV 38.5 dB 2096 848
21 Locked QAM256 28 573000000 Hz 6.4 dBmV 38.5 dB 2366 820
22 Locked QAM256 29 579000000 Hz 6.4 dBmV 38.3 dB 3049 872
23 Locked QAM256 30 585000000 Hz 6.5 dBmV 38.2 dB 3395 868
24 Locked QAM256 31 591000000 Hz 6.7 dBmV 38.3 dB 3020 865
25 Locked QAM256 32 597000000 Hz 6.9 dBmV 38.3 dB 2797 885
26 Locked QAM256 33 603000000 Hz 7 dBmV 38.2 dB 3357 886
27 Locked QAM256 34 609000000 Hz 7.1 dBmV 38.2 dB 3559 908
28 Locked QAM256 35 615000000 Hz 7.2 dBmV 38.2 dB 3544 904
29 Locked QAM256 36 621000000 Hz 7.5 dBmV 38.1 dB 3670 894
30 Locked QAM256 37 627000000 Hz 7.7 dBmV 38.1 dB 3658 879
31 Locked QAM256 38 633000000 Hz 7.8 dBmV 38 dB 4006 895
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 17300000 Hz 45.3 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 23700000 Hz 45.8 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 30300000 Hz 46 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 36700000 Hz 45.8 dBmV
5 Locked ATDMA 5 1280 Ksym/sec 41200000 Hz 47 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
Downstream OFDM Channels
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 850000000 Hz 9.1 dBmV 37.0 dB 1108 ~ 2987 597187021 263635991 0
2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0
 
Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked 0 0 0 Hz 0 dBmV
2 Not Locked 0 0 0 Hz 0 dBmV
 
Current System Time:Mon Jun 29 08:01:21 2020
System Up Time:1 day 01:01:05
Highlighted
Expert

Re: High Latency and Packet Loss - Menlo Park

The upstream power has more wiggle room.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Highlighted
Regular Visitor

Re: High Latency and Packet Loss - Menlo Park

I finally got a truck roll to the house tomorrow.  They called me this afternoon and said they fixed something but nothing is fixed.  Quite frustrating.  Here is the latest ping and modem report.

 

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
 
Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 525000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enabled BPI+
IP Provisioning Mode Honor MDD honorMdd(4)
 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 20 525000000 Hz 5.9 dBmV 39 dB 92 0
2 Locked QAM256 17 507000000 Hz 5.6 dBmV 39.2 dB 56 0
3 Locked QAM256 18 513000000 Hz 5.8 dBmV 39.2 dB 66 0
4 Locked QAM256 19 519000000 Hz 5.8 dBmV 39.1 dB 78 0
5 Locked QAM256 21 531000000 Hz 6 dBmV 38.9 dB 97 0
6 Locked QAM256 22 537000000 Hz 6 dBmV 38.9 dB 110 0
7 Locked QAM256 23 543000000 Hz 6 dBmV 38.8 dB 138 0
8 Locked QAM256 24 549000000 Hz 6.2 dBmV 38.9 dB 105 0
9 Locked QAM256 25 555000000 Hz 6.3 dBmV 38.8 dB 124 0
10 Locked QAM256 26 561000000 Hz 6.4 dBmV 38.8 dB 105 0
11 Locked QAM256 27 567000000 Hz 6.6 dBmV 38.7 dB 139 0
12 Locked QAM256 28 573000000 Hz 6.7 dBmV 38.7 dB 164 0
13 Locked QAM256 29 579000000 Hz 6.7 dBmV 38.5 dB 254 0
14 Locked QAM256 30 585000000 Hz 6.8 dBmV 38.4 dB 237 0
15 Locked QAM256 31 591000000 Hz 7 dBmV 38.5 dB 233 0
16 Locked QAM256 32 597000000 Hz 7.2 dBmV 38.5 dB 194 0
17 Locked QAM256 33 603000000 Hz 7.3 dBmV 38.4 dB 237 0
18 Locked QAM256 34 609000000 Hz 7.3 dBmV 38.4 dB 251 0
19 Locked QAM256 35 615000000 Hz 7.5 dBmV 38.3 dB 237 0
20 Locked QAM256 36 621000000 Hz 7.8 dBmV 38.4 dB 258 0
21 Locked QAM256 37 627000000 Hz 8 dBmV 38.3 dB 283 0
22 Locked QAM256 38 633000000 Hz 8.1 dBmV 38.2 dB 292 0
23 Locked QAM256 39 639000000 Hz 8.4 dBmV 38.3 dB 258 0
24 Locked QAM256 40 645000000 Hz 8.4 dBmV 38.2 dB 304 0
25 Locked QAM256 41 651000000 Hz 8.5 dBmV 38.1 dB 308 0
26 Locked QAM256 42 657000000 Hz 8.5 dBmV 38.1 dB 288 0
27 Locked QAM256 43 663000000 Hz 8.7 dBmV 38.1 dB 250 0
28 Locked QAM256 44 669000000 Hz 8.9 dBmV 38.1 dB 287 0
29 Locked QAM256 45 675000000 Hz 8.9 dBmV 37.9 dB 259 0
30 Locked QAM256 46 681000000 Hz 9 dBmV 38.1 dB 307 0
31 Locked QAM256 47 687000000 Hz 9.4 dBmV 38.1 dB 252 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 1 5120 Ksym/sec 17300000 Hz 45 dBmV
2 Locked ATDMA 2 5120 Ksym/sec 23700000 Hz 45.5 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 30300000 Hz 46 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 36700000 Hz 45.5 dBmV
5 Locked ATDMA 5 1280 Ksym/sec 41200000 Hz 46.5 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
Downstream OFDM Channels
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 850000000 Hz 9.7 dBmV 37.1 dB 1108 ~ 2987 102567342 39224384 0
2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0
 
Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked 0 0 0 Hz 0 dBmV
2 Not Locked 0 0 0 Hz 0 dBmV
 
Current System Time:Tue Jun 30 19:52:43 2020

System Up Time:02:39:18

 

Ping trace is better but still way too high:

C:\Users\John>ping 8.8.8.8

Pinging 8.8.8.8 with 32 bytes of data:
Reply from 8.8.8.8: bytes=32 time=672ms TTL=117
Reply from 8.8.8.8: bytes=32 time=444ms TTL=117
Reply from 8.8.8.8: bytes=32 time=625ms TTL=117
Reply from 8.8.8.8: bytes=32 time=704ms TTL=117

Ping statistics for 8.8.8.8:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 444ms, Maximum = 704ms, Average = 611ms

 

 

Highlighted
Regular Visitor

Re: High Latency and Packet Loss - Menlo Park

Comcast ultimately fixed an issue in our node of the network.  That solved it.

Highlighted
Expert

Re: High Latency and Packet Loss - Menlo Park

Glad that it got straightened out. Good luck ! Now closing this thread.



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!