Virgin Media Community

[mwarby]

For the last couple of evenings I've been experiencing intermittent droputs (I can ping my third party router, but not 8.8.8.8). Tech support initially thought it was a cable issue which unplugging it appeared to fix, however issue has returned

Whilst I'm used to interpreting ADSL connection stats, DOCSIS stats I'm not so familar with. I suspect the connection is OK but only just hanging on(downsream error count doesn't look ideal).

Thanks in advance

Cable Modem StatusItem Status Comments

Acquired Downstream Channel (Hz)	403000000	Locked
Ranged Upstream Channel (Hz)	39399981	Locked
Provisioning State	Online

Refresh data

Downstream bonded channelsChannel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID

1	403000000	-0.2	38	256 qam	30
2	195000000	1.4	37	256 qam	8
3	203000000	1.4	37	256 qam	9
4	211000000	1	38	256 qam	10
5	227000000	0.5	36	256 qam	12
6	235000000	0.7	38	256 qam	13
7	243000000	1.7	38	256 qam	14
8	251000000	0.5	40	256 qam	15
9	259000000	1.2	38	256 qam	16
10	267000000	0.7	38	256 qam	17
11	275000000	0.7	38	256 qam	18
12	283000000	1.4	40	256 qam	19
13	291000000	0	38	256 qam	20
14	299000000	0.7	38	256 qam	21
15	307000000	0.9	38	256 qam	22
16	315000000	0.7	38	256 qam	23
17	323000000	1.4	40	256 qam	24
18	363000000	0.2	40	256 qam	25
19	371000000	0	38	256 qam	26
20	379000000	0	40	256 qam	27
21	387000000	0.5	40	256 qam	28
22	395000000	-0.7	38	256 qam	29
23	411000000	0.2	38	256 qam	31

Downstream bonded channelsChannel Locked Status RxMER (dB) Pre RS Errors Post RS Errors

1	Locked	38.9	1782	0
2	Locked	37.3	24544	313
3	Locked	37.3	14889	319
4	Locked	38.6	10924	141
5	Locked	36.3	25427	221
6	Locked	38.6	18515	56
7	Locked	38.9	13817	108
8	Locked	40.3	6550	9
9	Locked	38.9	6848	55
10	Locked	38.6	5857	7
11	Locked	38.9	7140	11
12	Locked	40.3	4568	11
13	Locked	38.6	4410	6
14	Locked	38.9	3674	6
15	Locked	38.9	3338	7
16	Locked	38.9	2974	2
17	Locked	40.3	2719	0
18	Locked	40.3	2201	0
19	Locked	38.9	1985	0
20	Locked	40.9	1835	0
21	Locked	40.3	1840	0
22	Locked	38.9	1909	0
23	Locked	38.9	1655	0

Refresh data

Upstream bonded channelsChannel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID

1	39399981	5.05	5120	64 qam	4
2	32599991	4.85	5120	64 qam	5
3	46200019	5	5120	64 qam	3
4	53700048	4.7	5120	64 qam	2

Upstream bonded channelsChannel 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

[-tony-]

downstream levels are good -6 +10 is the range - some noise on the line i would suggest as there [as you note] high pre and post rs errors on some channels - hub is sorting most of them

upstream looks to be the problem - 2 channels at 5+ - read that as 50+ - theres a bug in the firmware that has the decimal point in the wrong place - 50 is ok but only just - if that rises its likely the hub will drop the connection

try and look at the upstream the next time the connection drop and post the levels

also post the network log - i dont understand much of whats in them but others will likely comment

if it is the upstream you need a tech - you could do with one anyway to check if the noise can be sorted easily

[mwarby]

Refresh data
Network Log
Time Priority Description
10/06/2019 18:10:59 Warning! Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 18:11:0 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 18:35:13 Warning! Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 18:35:23 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 19:18:41 Warning! Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 19:18:46 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 19:42:43 Warning! Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 19:42:49 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 20:02:21 Warning! Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 20:02:29 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 20:29:0 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 20:29:22 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 21:10:16 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
10/06/2019 21:11:45 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
11/06/2019 01:29:31 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
11/06/2019 01:32:58 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
11/06/2019 06:53:0 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
11/06/2019 07:20:41 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
11/06/2019 16:37:40 Warning! Lost MDD Timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
11/06/2019 16:37:42 Warning! RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

[mwarby]

in mean time I'll untangle the cables a bit, might help

[jem101]

---

@mwarby wrote:

in mean time I'll untangle the cables a bit, might help

---

Well it can't harm but I don't think it'll help too much unless you happen to find a connection which seems to be a bit loose and you can (finger) tighten it up.

The downstream statistics are actually quite good power and S/N ratio wise, however you have a fair number of PreRS errors and they are mostly concentrated in the lower frequency channel (what shows as channel 1 is actually the highest frequency then it starts going up from 2), which is indicative of noise/interference getting in- there's more inherent noise at lower frequencies so these bands get preferentially affected.

The upstream power levels are right on the upper bounds of what's acceptable, the MDD Timeouts are indicative of the modem having trouble talking and the RCS Partial Service is the modem losing some of the channels entirely.

What I suspect is that you have a bad connection or damaged cable somewhere in the run back to the cabinet, it may be inside your house or in the box outside where the coax cable comes up, this is allowing noise to enter the circuit, the upstream power levels rise to try to compensate and if they reach a certain threshold value, the modem will reset to try to renegotiate a better connected - rinse and repeat.

You'll need an engineer visit to check it all, either call it in although you may have to go through the 'change wifi channels' etc. before persuading them to send an engineer out. Alternatively hold-fire until one of the forum team find this thread and contacts you directly to arrange things.

Best wishes

John

[mwarby]

I did notice the exterior connection, which come from a neighboring property seems to be a little damaged. The  cover is off and you can see f plugs joining cable. The neighbors kids seem to keep their scooters next to it too

Not sure how virgin would go about fixing an issue on a nieghbors property

[mwarby]

I have to say its a real shame that the tech support staff seem not to be able to interpret the modems stats nearly as well as fellow users. Thanks for help. The cable rejig did nothing, but at least it rules it out

[Hetty_R]

Hi mwarby, 

Welcome to our community forums and thank you for taking the time to get in touch! 

I am really sorry to see you're having problems with your broadband connection,  I have had a quick look at our end and can't see any obvious issues. I will send you a private message so we can get your details and investigate this further.

Please look out for a purple envelope in the top corner and reply when you can 🙂 

Look forward to hearing from you, 

[mwarby]

I dont see a purple icon, and I dont seem to have any PMs

Checking modem logs this morning I saw some new errors overnight under network logs, which jem101 said would indicative of dropouts

[-tony-]

---

@mwarby wrote:

I did notice the exterior connection, which come from a neighboring property seems to be a little damaged. The  cover is off and you can see f plugs joining cable. The neighbors kids seem to keep their scooters next to it too

Not sure how virgin would go about fixing an issue on a nieghbors property

---

a connection from next door will be no problem to them - they will just barge in and look - maybe knock on his door maybe not

but your comment raises a question - why are you connected from next door - that in itself may not have any bearing on your problems but a connection like that should only be done as a temp measure unless there are big problems giving you your own drop cable - block paving drives - crossing land they have no permission to cross - flats and a few other reasons

if you have your own drop point on the pavement and the cable from there can be routed across your land then you should push for that