Slow speeds during peak times - Slower speed after work was completed in my area

[Cyirak]

Over the past couple of weeks the achievable speed seem to have dropped on my broadband. I recently upgraded from M350 to M500 package. 

To build a bit of background..

Stupidly or not, I upgraded whilst there was multiple issues in my area but just so happened to be when I decided to do it. We were experiencing high packet loss, with periods of 50% loss at times or complete loss of service this was before and after the upgrade... We had an engineer come out and he checked the cable all the way from the Hub back to the cabinet and he advised that there were no issues with our line however he picked up on an issue that was effecting everyone down our road. Even with these issues in place my download was always 520Mbps+ even at peak times, however my upload was shot and sometimes wouldn't even hit 10Mbps.

The issues have now been resolved and stability wise, no packet loss or loss of service which is great however I'm finding my downloads speeds aren't as good as before the issue was resolved.  Sometimes only getting about 200mbps at peak times where as my friend about a mile away is getting full speed. I also noticed that the downstream power levels have dropped from around 4.x to 2.x. Upstream power seems to have stayed the same.

Before I call virgin and raise a issue I wanted to check if the stats are okay on my downstream and upstream..

Any help or advise would be appreciated. 

Stats are since Monday 14th June about 5 days of uptime on the modem.

There are RCS partial service in the logs however these were logged prior to me receiving notification on the 14th that the problem had been resolved.

Downstream bonded channels

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

1	234750000	2.2	38	256 qam	13
2	242750000	1.9	38	256 qam	14
3	250750000	1.9	38	256 qam	15
4	258750000	2	38	256 qam	16
5	266750000	2.2	38	256 qam	17
6	274750000	2.2	39	256 qam	18
7	282750000	2.5	40	256 qam	19
8	290750000	2.7	40	256 qam	20
9	298750000	2.9	38	256 qam	21
10	306750000	2.7	40	256 qam	22
11	314750000	3	38	256 qam	23
12	322750000	3.2	40	256 qam	24
13	330750000	3	40	256 qam	25
14	338750000	2.7	40	256 qam	26
15	346750000	2.7	40	256 qam	27
16	354750000	2.7	40	256 qam	28
17	362750000	2.7	40	256 qam	29
18	370750000	2.9	39	256 qam	30
19	378750000	3	38	256 qam	31
20	386750000	2.7	38	256 qam	32
21	394750000	2.5	38	256 qam	33
22	402750000	2.2	38	256 qam	34
23	410750000	2.2	38	256 qam	35
24	418750000	2.2	38	256 qam	36

Downstream bonded channels

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

1	Locked	38.9	182395	794
2	Locked	38.9	121045	393
3	Locked	38.9	74704	135
4	Locked	38.9	45207	21
5	Locked	38.9	25763	0
6	Locked	39.8	13596	0
7	Locked	40.3	7574	0
8	Locked	40.3	4334	0
9	Locked	38.9	2875	0
10	Locked	40.3	1958	0
11	Locked	38.9	2390	0
12	Locked	40.3	2810	0
13	Locked	40.3	2908	0
14	Locked	40.3	3514	0
15	Locked	40.3	3695	0
16	Locked	40.3	3743	0
17	Locked	40.9	3703	0
18	Locked	39.8	4074	0
19	Locked	38.9	4788	0
20	Locked	38.9	4570	0
21	Locked	38.9	3094	0
22	Locked	38.6	2029	0
23	Locked	38.9	912	0
24	Locked	38.6	376	0

Upstream bonded channels

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

1	60299899	38.8	5120	64 qam	1
2	39399994	38.3	5120	64 qam	4
3	46200055	38.3	5120	64 qam	3
4	53699819	38.5	5120	64 qam	2

Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1	ATDMA	0	0	1	0
2	ATDMA	0	0	1	0
3	ATDMA	0	0	0	0
4	ATDMA	0	0	0	0

Network Log
Time Priority Description
18/06/2021 06:27:7 critical No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
17/06/2021 12:40:38 Error DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
14/06/2021 17:17:40 notice LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

[Zak_M]

Good afternoon @Cyirak 

I have just had a quick check over the account, the resolve to the SNR issue has been pushed back to tomorrow, SNR issue are notoriously difficult to resolve as it could be any number of things to causing it. 

We are sorry for the inconvenience that this has caused. 

Kind regards,

Zak_M

[Cyirak]

Hi Zak,

Thanks for the update you saved me some time calling customer services to check on the progress of this. I'll wait until Thursday and check in to see if this has been resolved. 

Kind Regards

[Andrew-G]

Strange that the problem keeps on mysteriously being booted into the future, when resolving an SNR problem really ought to be absolute basics for the operators of an analogue closed circuit RF network.  I'll suggest again that it might be worth running a BQM and posting a link here.  

[Cyirak]

Hi Andrew,

Thanks for the suggestion. I currently run something similar though its not think broadband. I can see evidence of packet loss when i experience issues, the problem is really intermittent and if i start getting issues (TCP traffic seems fine though slower due to re-transmits but UDP traffic such as voice or gaming really suffers) i can typically look at the router statistics and see that the upstream modulation has dropped typically on 2 or more channels, the problem can last 6 minutes or 6 hours, I've not established any pattern but  various engineers have been out and have seen issues upstream which unfortunately they aren't able to do anything about and need to involve the networks team. At the moment i would like to see the fault being cleared so i can then troubleshoot without any known issue outstanding, however this has been going on for months and typically once a network fault is closed another one is raised shortly after, so i wont be holding my breath! 

Thanks for taking the time to respond.

Kind Regards

[Andrew-G]

I'd be suspicious that the problem might be over-utilisation, and that's why I was suggesting a BQM.  

[Cyirak]

Hi Andrew, 

I see what you're saying now. 

so heres a link to my broadband,

as you can see its fairly noisy this is a pretty good day where i only noticed a few minutes of disruption at around 17:30, for comparison this is a friends Virgin broadband that lives about 5 miles away 

and lastly my parents but they are on BT FTTP which is nice and clean, unfortunately bt fftp isn't available where i live

[Andrew-G]

Cheers - the good news is there's no sign of a utilisation fault, and the bad news is that you're no nearer a fix!

[Cyirak]

Yeah one of those things. thanks for taking a look. 

Speeds seem fine most the time. Real shame as for the last few years the service has been solid. 

[Cyirak]

Good Afternoon,

Could someone from virgin media confirm if the SNR outage has been resolved?

it appears the upstream modulation has dropped and i noticed as i experienced a very brief loss of service

Upstream bonded channels

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

1	60300357	43	5120	32 qam	1
2	46199502	42.3	5120	32 qam	3
3	39399985	42.3	5120	32 qam	4
4	53700175	42.5	5120	32 qam	2

[Cyirak]

Just Spoken with CS. Seems that the issue has been closed and presumably resolved fingers crossed it has actually been fixed this time but no issues yesterday and today so fingers crossed.