Virgin Media Community

[Dangermouse1248]

I’m on M100. For weeks now (months?) upload speed drops from a fairly stable rate of ~10Mbps to 0.05-1.5Mbps every night, from around 21:30BST.

How many others see the same and is VM doing anything to fix it?

Thanks - Paul.

[MikeRobbo]

How are you connecting your device, Wi-Fi or ethernet cable ?

It can be difficult diagnosing problems without some basic information.

Have you checked the 'Check Service Status' at the top of the page ?

If nothing is showing try phoning 0800 561 0061, this will tell you of more local issues that may be affecting the area. Be aware that it isn't a manned line.

Go round all the accessible co-ax connections and ensure that they are finger tight.

If everything above is OK we need do some troubleshooting; to start with …

Can you set up a Broadband Quality Monitor (BQM) at thinkbroadband.com - this will give you an insight into what is happening with the signal at the other side of the Hub, it will take a few hours to get any kind of trend showing although you should post the link straight away.

Post a link to your BQM on here.

Instructions for posting BQM Link

Under your BQM graph are two links in red.

Click the lower link (Share Live Graph) then click generate.

Copy the text in the Direct Link box, beware, there may be more text than you can see.

On here click the Link icon (2 links chain to the left of the camera icon)

In the URL box paste the link you copied and in the ‘text to display’ box write My BQM then click OK - you can post the link straight away.

Then

Can you please

Type 192.168.0.1 (192.168.100.1 in Modem mode) into your browser URL bar and press enter. 

When the page appears DO NOT LOG IN but click ‘Check Router Status’.

Copy and paste the contents of the Downstream, Upstream and Network Log tabs onto here, if you get a yellow warning click the Post button again.

A Guru will be along soon to decipher the info.

[Dangermouse1248]

Test post - please ignore

[Dangermouse1248]

Hello Mike,

Thanks for your reply.  I mainly use 802.11ac WiFi but have also checked this matches a directly-wired connection (ac/5GHz on a low-utilisation network with few neighbourhood interferers is, of course, more than capable of matching the M100 bit rate [802.11n on 2.4GHz won't of course ... but yes, I did check against a wired link).  The daily pattern is very predictable;  close to 100Mb/s download and close to 10Mb/s upload all day, every day except for 21:30 (+/- a few minutes) until the early hours when download is usually "OK" but upload is terrible (usually below 1Mb/s, often a fraction of even that).  Speed measurement is made using a few of the popular online speed tests (Ookla and similar) - all seem to give results consistent with each other.

VM sent a new Hub3 to see if that would help but it made no difference.  All the usual stuff like coax connections are OK/tight (and manage to work fine every day except for the "bad" hours).

I regularly check the "Check service status" link.  With the old SuperHub, running the line tests would often result in a message saying there's an interference problem affecting the VM network and impacting customers in my area ... since the new Hub3 arrived, running the tests always returns an "everything's fine" response full of green happy-looking ticks.

I did set up a BQM monitor a few days ago.  The live graph is at:

https://www.thinkbroadband.com/broadband/monitoring/quality/share/ed62ee49cb5023bf4d59fd13e403b41ff716324f

The router status/logs have been taken both when working OK (19:36 tonight) and also while the problem exists (21:52 this evening) and, along with an Ookla speed test in each case.  I'm having trouble posting so the logs need to be text (sorry):

WHEN WORKING OK; Ookla: 112.93Mb/s down, 10.05Mb/s up (19:36BST 25-aug-2020)

Downstream bonded channels (*system working OK*)

Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID

1 410250000 6 38 256 qam 1
2 418250000 6 38 256 qam 2
3 426250000 6 38 256 qam 3
4 434250000 5.9 38 256 qam 4
5 442250000 5.8 38 256 qam 5
6 450250000 5.9 38 256 qam 6
7 458250000 5.9 38 256 qam 7
8 466250000 5.6 38 256 qam 8
9 474250000 5.6 38 256 qam 9
10 482250000 6 38 256 qam 10
11 490250000 5.8 38 256 qam 11
12 498250000 5.5 38 256 qam 12
13 506250000 5.1 38 256 qam 13
14 514250000 5 38 256 qam 14
15 522250000 4.8 38 256 qam 15
16 530250000 4.5 38 256 qam 16
17 538250000 4 38 256 qam 17
18 546250000 3.9 38 256 qam 18
19 554250000 4.1 38 256 qam 19
20 562250000 4.5 38 256 qam 20
21 570250000 4.3 38 256 qam 21
22 578250000 4 38 256 qam 22
23 586250000 4.5 38 256 qam 23
24 594250000 4 37 256 qam 24

Downstream bonded channels (*system working OK*)

Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors

1 Locked 38.6 1560028 80060
2 Locked 38.6 1388193 77428
3 Locked 38.9 1304455 83728
4 Locked 38.9 1207255 89350
5 Locked 38.6 1145343 89954
6 Locked 38.6 1028133 84106
7 Locked 38.6 952880 87900
8 Locked 38.6 907021 99226
9 Locked 38.9 851592 90523
10 Locked 38.6 753466 93255
11 Locked 38.9 696595 91168
12 Locked 38.6 634988 93844
13 Locked 38.9 592785 96676
14 Locked 38.9 557602 98832
15 Locked 38.9 507445 88361
16 Locked 38.9 460999 90473
17 Locked 38.6 430833 90528
18 Locked 38.6 406257 93518
19 Locked 38.9 364319 89942
20 Locked 38.6 334242 90564
21 Locked 38.6 314754 89770
22 Locked 38.6 293045 87554
23 Locked 38.6 267617 87995
24 Locked 37.6 255177 83210

Upstream bonded channels (*system working OK*)
Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
1 39400008 3.8 5120 64 qam 6
2 46200023 3.875 5120 64 qam 5
3 25800124 3.8289999999999997 5120 64 qam 8
4 32600018 3.8 5120 64 qam 7

Upstream bonded channels (*system working OK*)
Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts
1 ATDMA 0 0 0 0
2 ATDMA 0 0 0 0
3 ATDMA 0 0 0 0
4 ATDMA 0 0 0 0

Network Log (*system working OK*)
Time Priority Description
24/08/2020 23:00:12 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 06:09:20 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 06:09:20 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 06:09:17 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 06:09:17 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 05:44:2 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 05:44:2 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 05:30:33 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 05:30:33 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:55:11 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:55:11 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:52:57 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:52:57 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:44:24 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:44:24 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:36:24 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:36:24 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:33:43 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:33:42 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:31:36 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

WHEN NOT WORKING OK;  Ookla: 102.36Mb/s down, 0.34Mb/s up (21:52BST 25-aug-2020)

Downstream bonded channels (*system not working OK - bad upload speed*)
Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
1 410250000 6.3 38 256 qam 1
2 418250000 6.3 38 256 qam 2
3 426250000 6.1 38 256 qam 3
4 434250000 6 38 256 qam 4
5 442250000 6 38 256 qam 5
6 450250000 6.1 38 256 qam 6
7 458250000 6.1 38 256 qam 7
8 466250000 5.9 38 256 qam 8
9 474250000 5.9 38 256 qam 9
10 482250000 6.1 38 256 qam 10
11 490250000 6 38 256 qam 11
12 498250000 5.9 38 256 qam 12
13 506250000 5.4 38 256 qam 13
14 514250000 5.3 38 256 qam 14
15 522250000 5 38 256 qam 15
16 530250000 4.8 38 256 qam 16
17 538250000 4.3 38 256 qam 17
18 546250000 4.1 38 256 qam 18
19 554250000 4.5 38 256 qam 19
20 562250000 4.8 38 256 qam 20
21 570250000 4.5 38 256 qam 21
22 578250000 4.4 38 256 qam 22
23 586250000 4.6 38 256 qam 23
24 594250000 4.4 37 256 qam 24

Downstream bonded channels (*system not working OK - bad upload speed*)
Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1 Locked 38.6 1560028 80060
2 Locked 38.6 1388193 77428
3 Locked 38.9 1304455 83728
4 Locked 38.9 1207255 89350
5 Locked 38.6 1145343 89954
6 Locked 38.6 1028133 84106
7 Locked 38.6 952880 87900
8 Locked 38.6 907021 99226
9 Locked 38.9 851592 90523
10 Locked 38.6 753466 93255
11 Locked 38.9 696595 91168
12 Locked 38.6 634988 93844
13 Locked 38.9 592785 96676
14 Locked 38.9 557602 98832
15 Locked 38.9 507445 88361
16 Locked 38.9 460999 90473
17 Locked 38.6 430833 90528
18 Locked 38.6 406257 93518
19 Locked 38.9 364319 89942
20 Locked 38.6 334242 90564
21 Locked 38.6 314754 89770
22 Locked 38.6 293045 87554
23 Locked 38.6 267617 87995
24 Locked 37.6 255177 83210

Upstream bonded channels (*when system not working OK - bad upload speed*)
Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
1 39400008 3.8 5120 64 qam 6
2 46200023 3.875 5120 64 qam 5
3 25799828 3.825 5120 16 qam 8
4 32600038 3.8 5120 64 qam 7
 

Upstream bonded channels (*system not working OK - bad upload speed*)
Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts
1 ATDMA 0 0 0 0
2 ATDMA 0 0 0 0
3 ATDMA 0 0 0 0
4 ATDMA 0 0 0 0

Network Log (*system not working OK - bad upload speed*)
Time Priority Description
24/08/2020 23:00:12 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 06:09:20 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 06:09:20 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 06:09:17 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 06:09:17 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 05:44:2 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 05:44:2 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 05:30:33 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 05:30:33 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:55:11 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:55:11 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:52:57 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:52:57 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:44:24 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:44:24 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:36:24 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:36:24 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:33:43 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:33:42 critical SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
24/08/2020 04:31:36 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

I've been a Virgin Media customer for over 10 years - this is the 1st time I've started researching 4G/5G mobile hotspots as a potential alternative to VM.  I hope the guru you mention has some good ideas and makes further research unnecessary 🙂

Thanks for your interest and help.

[Emma_C]

Hi Dangermouse1248, 

Really sorry about the issues you've been having and for the delay in getting back to you. 

Have things improved since your post? 

If not then are you able to post another log for us please?

[Dangermouse1248]

Well, I’m not sure what happened but credit where it’s due ...both download and upload speeds have been pretty much as they should be both during the day and during what used to be the “bad” times (around 21:30BST for the rest of the night/early hours).  I’ll keep monitoring it but a good result so far at least.

- Paul.