Been using my M500 broadband line for a few years now and never had problems with Virgin Media, until two weeks ago. I started getting random latency spikes that's deeply affecting work calls and gaming.Engineer came around on Saturday and says everything is "fine" on my line, even replaced my Hub 3 router with a brand new one - after he left, I continued to monitor and test for a few hours, but sadly same issue persists! I've set up a BQM (I showed the engineer this, but didn't seem phased)Here is my line with the BQM from ThinkBroadband (post the new Hub 3 as the graph looked the same pre-new Hub 3), you can clearly see the dropped packets - Clearly there is something very wrong with my line, please can anyone help!?

Update: My line is all fixed. The second engineer visited this morning and I told him about the first engineer visit and the Hub 3 router replacement the first engineer did.The second engineer could see the issues on his diagnostic device - the issue seemed to stem from the coaxial cable wiring inside my house (from the outside brown box). He replaced the entire coaxial wiring with fibre and fit a new coaxial converter at the end (I'm still Hub 3). After a 45 min job and a line diagnostic on his end, he could see the issue resolved on his diagnostic device.Suddenly my packet loss/latency issues are resolved, here is the upgraded graph - you can see the night/day different after the 8am downtime:Latency and packet loss issues are now resolved. It seemed the solution was to replace the old coaxial wiring with fibre and fix a new coaxial converter for the Hub 3.

Latency spikes/dropped packets, at wits end! | Virgin Media Community

20 Replies

Cardiffman282
Community elder
22 days ago
Anything come up when you check for local faults on 0800 561 0061?
- spaceman85
  On our wavelength
  22 days ago
  No faults in the area - website also doesn't report any issues in my area. The engineer also checked this and this has been ongoing for weeks :/
spaceman85
On our wavelength
22 days ago
If this helps, I'll leave diagnostic info below from the Hub 3 router:

Status:
Item Status Comments
Acquired Downstream Channel (Hz)
330750000
Locked
Ranged Upstream Channel (Hz)
32600045
Locked
Provisioning State
Online

Item	Status	Comments
Acquired Downstream Channel (Hz)	330750000	Locked
Ranged Upstream Channel (Hz)	32600045	Locked
Provisioning State	Online

spaceman85

On our wavelength

22 days ago

Downstream:

Channel	Frequency (Hz)	Power (dBmV)	SNR (dB)	Modulation	Channel ID
1	330750000	3.5	40	256 qam	25
2	202750000	5.3	40	256 qam	9
3	210750000	5	38	256 qam	10
4	218750000	5	40	256 qam	11
5	226750000	4.9	40	256 qam	12
6	234750000	4.8	40	256 qam	13
7	242750000	4.5	40	256 qam	14
8	250750000	4.3	39	256 qam	15
9	258750000	4.1	40	256 qam	16
10	266750000	4.1	40	256 qam	17
11	274750000	3.9	40	256 qam	18
12	282750000	3.9	40	256 qam	19
13	290750000	3.7	39	256 qam	20
14	298750000	3.7	40	256 qam	21
15	306750000	3.5	40	256 qam	22
16	314750000	3.5	38	256 qam	23
17	322750000	3.5	40	256 qam	24
18	338750000	3.7	40	256 qam	26
19	346750000	3.7	40	256 qam	27
20	354750000	3.5	38	256 qam	28
21	362750000	3.7	40	256 qam	29
22	370750000	3.7	40	256 qam	30
23	378750000	3.9	38	256 qam	31
24	386750000	4	40	256 qam	32

Channel	Locked Status	RxMER (dB)	Pre RS Errors	Post RS Errors
1	Locked	40.3	114848	1020858
2	Locked	40.3	107939	1028723
3	Locked	38.9	109984	1028096
4	Locked	40.3	103364	1035492
5	Locked	40.9	109908	1026676
6	Locked	40.3	107647	1029208
7	Locked	40.3	108436	1032650
8	Locked	39.8	108188	1026851
9	Locked	40.3	108097	1024280
10	Locked	40.9	104082	1037952
11	Locked	40.3	105847	1026394
12	Locked	40.3	111519	1027534
13	Locked	39.3	122983	1010542
14	Locked	40.3	123288	1009278
15	Locked	40.3	111037	1030167
16	Locked	38.9	119263	1029699
17	Locked	40.3	117876	1026499
18	Locked	40.3	125179	1007362
19	Locked	40.3	123006	1018636
20	Locked	38.9	126810	1015773
21	Locked	40.3	128807	1007875
22	Locked	40.3	126624	1009435
23	Locked	38.9	131309	1015920
24	Locked	40.3	129947	1010802

Cardiffman282
Community elder
21 days ago
The high Post RS Errors across all channels suggest ingress noise and/or faulty cabling. Have you checked that all your cables and connections visible to you internally and externally are in good order?
- spaceman85
  On our wavelength
  21 days ago
  My cables are all fine from what I can tell. The Virgin Media engineer ran a diagnostic on my line on Saturday, checked my Virgin Box outside and claimed all was good.

spaceman85

On our wavelength

22 days ago

Upstream:

Channel	Frequency (Hz)	Power (dBmV)	Symbol Rate (ksps)	Modulation	Channel ID
1	32600045	31.4	5120	64 qam	11
2	23600150	31.3	5120	64 qam	12
3	39400440	31	5120	64 qam	8
4	46200409	30.8	5120	64 qam	7
5	53700346	30.8	5120	64 qam	6
6	60300557	31	5120	64 qam	5

Channel	Channel Type	T3 Timeouts
1	ATDMA	6
2	ATDMA	7
3	ATDMA	9
4	ATDMA	8
5	ATDMA	6
6	ATDMA	7

spaceman85
On our wavelength
22 days ago
Config

General Configuration
Network access
Allowed
Maximum Number of CPEs
1
Baseline Privacy
Enabled
DOCSIS Mode
Docsis30
Config file
cmreg-vmdg505-bbt053-b.cm

Primary Downstream Service Flow
SFID 44562
Max Traffic Rate 575000000
Max Traffic Burst 42600
Min Traffic Rate 0

Primary Upstream Service Flow
SFID 44561
Max Traffic Rate 55000085
Max Traffic Burst 42600
Min Traffic Rate 0
Max Concatenated Burst 42600
Scheduling Type BestEffort

spaceman85

On our wavelength

21 days ago

Network Log (mac omitted)

Time	Priority	Description
20/10/2025 14:08:44	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 14:08:39	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 14:06:25	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 14:06:24	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 14:06:7	notice	LAN login Success;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 14:05:17	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 14:04:40	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 14:00:26	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 14:00:26	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:52:18	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:52:18	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:49:49	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:49:40	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:48:2	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:47:42	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:46:25	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:46:25	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:46:25	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:46:14	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;
20/10/2025 13:42:29	Warning!	RCS Partial Service;CM-MAC=omitted;CMTS-MAC=omitted;CM-QOS=1.1;CM-VER=3.0;

spaceman85
On our wavelength
21 days ago
Today's view. same issues:
https://www.thinkbroadband.com/broadband/monitoring/quality/share/d350974cd6dc2e65f7c0a7419c361b51547eafe6
legacy1
Alessandro Volta
21 days ago
Maybe your being pulse DoS which is short floods.
Setup in modem mode with a PC and a new BQM allow ICMP inbound on windows firewall from remote IP 80.249.99.164 for some hours with light use.
- spaceman85
  On our wavelength
  21 days ago
  Thanks for the tip, so I tried this but you can see the same issue persists. I doubt it's a DoS as the IP for the alt router is different, yet the same dropped packets occur
  - jpeg1
    Alessandro Volta
    20 days ago
    I'm surprised that you can get any use at all with a BQM like that. The problem is definitely outside.
spaceman85
On our wavelength
21 days ago
Might be getting somewhere as Virgin now confirms Intermittent signal in the area. I guess it's a waiting game now
Rajj77
Joining in
20 days ago
We are having the same problem and have been for about 2 weeks , had numerous engineers out , changed hub 5 and yet problem persists , finally one of the engineers told me that it deffo is a problem on their side , something to do with firmware update , no idea how long it will take to fix , end of my tether tbh
- spaceman85
  On our wavelength
  20 days ago
  Interesting, that time frame aligns with the time around when mine started playing up. Thank you for the info
  - Rajj77
    Joining in
    19 days ago
    Another engineer came today and told me that it only affects Hub 5’s , they have acknowledged the problem and reckons it should be fixed in the next 2/3 days , if I get any more info I’ll let you know