Virgin Media Community

[geoffrey_t]

I've been working from home during COVID lockdown and audio/video calls are completely useless frequently breaking down for 10s of seconds at a time. This is so awkward that I bought a 4G router and have had to use that for work.

Running an outbound ping continually from my machine shows that the latency is pretty decent at about 15-20ms most of the time, but often spikes to 500-700ms which completely kills any ability to operate on calls. I've even noticed netflix downgrading to potato quality which means the drops can be quite sustained since there should be a buffer. Lots of post-rs errors too.

BQM:

Status

Acquired Downstream Channel (Hz)	323000000	Locked
Ranged Upstream Channel (Hz)	32600000	Locked
Provisioning State	Online

Downstream bonded channels

Channel	Frequency (Hz)	Power (dBmV)	SNR (dB)	Modulation	Channel ID
1	323000000	0.5	40	256 qam	24
2	139000000	3.2	38	256 qam	1
3	147000000	3.5	40	256 qam	2
4	155000000	2.5	40	256 qam	3
5	163000000	3	40	256 qam	4
6	171000000	3.2	40	256 qam	5
7	179000000	3.2	40	256 qam	6
8	187000000	2.9	40	256 qam	7
9	195000000	2.2	40	256 qam	8
10	203000000	2.4	40	256 qam	9
11	211000000	2.2	40	256 qam	10
12	219000000	2.2	40	256 qam	11
13	227000000	2.2	40	256 qam	12
14	235000000	1.7	40	256 qam	13
15	243000000	1.5	40	256 qam	14
16	251000000	1.2	40	256 qam	15
17	259000000	1.2	40	256 qam	16
18	267000000	1.2	40	256 qam	17
19	275000000	1.2	40	256 qam	18
20	283000000	1.2	40	256 qam	19
21	291000000	1.2	40	256 qam	20
22	299000000	1.2	40	256 qam	21
23	307000000	1	40	256 qam	22
24	315000000	0.7	40	256 qam	23

Channel	Locked Status	RxMER (dB)	Pre RS Errors	Post RS Errors
1	Locked	40.3	3759	164899
2	Locked	38.9	21171	304709
3	Locked	40.9	58273	267820
4	Locked	40.9	62492	265668
5	Locked	40.9	53126	275985
6	Locked	40.9	18724	309508
7	Locked	40.3	18969	309892
8	Locked	40.3	9395	315459
9	Locked	40.9	6740	320828
10	Locked	40.3	4371	318253
11	Locked	40.3	3377	318277
12	Locked	40.9	2966	303998
13	Locked	40.3	2744	303639
14	Locked	40.9	2814	309715
15	Locked	40.3	2906	300909
16	Locked	40.3	3399	267466
17	Locked	40.3	2816	292805
18	Locked	40.9	3405	260705
19	Locked	40.3	2488	316903
20	Locked	40.3	2789	302644
21	Locked	40.3	2934	300021
22	Locked	40.3	2559	168054
23	Locked	40.9	2565	215809
24	Locked	40.9	2075	93676

[geoffrey_t]

Upstream

Channel	Frequency (Hz)	Power (dBmV)	Symbol Rate (ksps)	Modulation	Channel ID
1	32600000	4.05	5120	64 qam	5
2	39400000	4.15	5120	64 qam	4
3	46200000	4.15	5120	64 qam	3
4	53700000	4.2	5120	64 qam	2

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

General Confiuration

Network access	Allowed
Maximum Number of CPEs	1
Baseline Privacy	Enabled
DOCSIS Mode	Docsis30
Config file	kldJKDHSUBsgvca69834ncxv98732

Primary downstream service flow

SFID	10578
Max Traffic Rate	117000047
Max Traffic Burst	42600
Min Traffic Rate	0

Primary upstream service flow

SFID	6112
Max Traffic Rate	10500047
Max Traffic Burst	16320
Min Traffic Rate	0
Max Concatenated Burst	16320
Scheduling Type	BestEffort

[geoffrey_t]

Network log

Time	Priority	Description
14/06/2020 06:15:4	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
13/06/2020 15:04:24	notice	DHCP Renew - lease parameters tftp file-cmreg-vmdg505-rtsl10016u-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
13/06/2020 15:04:24	Error	DHCP REBIND WARNING - Field invalid in response;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
13/06/2020 12:13:54	Error	DHCP RENEW sent - No response for IPv4;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
13/06/2020 10:56:14	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
13/06/2020 09:23:27	Error	DHCP RENEW sent - No response for IPv4;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
13/06/2020 09:07:45	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
13/06/2020 03:42:34	Error	DHCP RENEW sent - No response for IPv4;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 17:34:34	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 16:20:47	Error	DHCP RENEW sent - No response for IPv4;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 11:03:43	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 11:03:43	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 11:03:42	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 11:03:39	Warning!	Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 11:03:35	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 11:03:35	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 11:03:34	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 10:28:28	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 10:28:28	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
12/06/2020 10:28:27	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

[DJ_Shadow1966]

Hello

Post RS errors are noormally indicitive of noise on the line, in cases like this go around and make sure all coaxial connectors to all VM equipment are finger tight, also checking that there are no unterminated connections or damage/sharp bends to the cable.

Power off hub for 30 secs and back on if the post RS errors are increasing still at a vast rate then an engineer will be need to find the cause of the noise.

Regards Mike

[geoffrey_t]

12 hours later and the post-rs errors haven't increased but I have still been having issues, the BQM graph looks pretty ropey, and my outbound ping requests still sometimes jump to 500-700ms for anything from 1-60seconds at a time.

I checked connections and restarted the modem now, but assuming we don't see any more post-rs errors then there must be another cause.

[Chris_W1]

HI Geoffrey, thanks for messaging us and we are sorry to see that you are having issues with the service. We will send you a private message to have a closer look. ^Chris. 

[geoffrey_t]

Had the visit on Saturday, and the engineer inspected and reterminated a bunch of the connectors, measured the slope of the signal (attenuation at higher frequencies) and replaced the 3db attenuator with an equalizer to reduce the slope a bit, but wasn't really of the opinion that any of this would fix the issue. It's always difficult with an intermittent issue as you can't tell if it's fixed immediately.

Things looked relatively good over the weekend but I suspect that's just lower overall traffic volumes at the weekend. Today we had a full outage while a Virgin Media van was parked further up the road so there is clearly more work ongoing. I'll leave it another few days to see if that maintenance may have changed anything.