1gig lost Docsis 3.1 channels

[siopoudis]

I've had a new 1Gig line installed about 2 months ago, and everything was working well, was getting > 1000mbps speed on Virgin's speed test (samknows)

Today, speed is down to 44Mbps and router reports no DOCSIS 3.1 channels connected. Restarting the router hasn't helped at all, and Virgin's website indicates no issues in my area (KT3)
It also doesn't let me book an engineer since it thinks everything is ok apparently?

[siopoudis]

Adding the SamKnows speed test in modem mode and the channels

3.0 Downstream channels

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

25	331000000	4	40.4	QAM256	25
1	139000000	5.7	39	QAM256	1
2	147000000	5.6	39	QAM256	2
3	155000000	5.4	40.4	QAM256	3
4	163000000	5	40.4	QAM256	4
5	171000000	4.7	39	QAM256	5
6	179000000	4.2	40.4	QAM256	6
7	187000000	4	40.4	QAM256	7
8	195000000	4	39	QAM256	8
9	203000000	3.9	40.4	QAM256	9
10	211000000	3.7	40.4	QAM256	10
11	219000000	3.7	40.9	QAM256	11
12	227000000	3.7	40.9	QAM256	12
13	235000000	3.8	40.4	QAM256	13
14	243000000	4.4	40.4	QAM256	14
15	251000000	4.4	40.4	QAM256	15
16	259000000	4.3	40.4	QAM256	16
17	267000000	4.4	40.4	QAM256	17
18	275000000	4.7	40.4	QAM256	18
19	283000000	4.1	40.4	QAM256	19
20	291000000	3.8	40.4	QAM256	20
21	299000000	4.3	40.4	QAM256	21
22	307000000	4.5	40.4	QAM256	22
23	315000000	4	40.4	QAM256	23
24	323000000	3.8	40.9	QAM256	24
26	339000000	3.6	40.9	QAM256	26
27	347000000	3.1	40.9	QAM256	27
28	355000000	3.1	40.4	QAM256	28
29	363000000	3.5	40.9	QAM256	29
30	371000000	2.9	40.4	QAM256	30
31	379000000	2.4	40.9	QAM256	31

3.0 Downstream channels

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

25	Locked	40.366287	0	0
1	Locked	38.983261	0	0
2	Locked	38.983261	0	0
3	Locked	40.366287	0	0
4	Locked	40.366287	0	0
5	Locked	38.983261	0	0
6	Locked	40.366287	0	0
7	Locked	40.366287	0	0
8	Locked	38.983261	0	0
9	Locked	40.366287	0	0
10	Locked	40.366287	0	0
11	Locked	40.946209	0	0
12	Locked	40.946209	0	0
13	Locked	40.366287	0	0
14	Locked	40.366287	0	0
15	Locked	40.366287	0	0
16	Locked	40.366287	0	0
17	Locked	40.366287	0	0
18	Locked	40.366287	0	0
19	Locked	40.366287	0	0
20	Locked	40.366287	0	0
21	Locked	40.366287	0	0
22	Locked	40.366287	0	0
23	Locked	40.366287	0	0
24	Locked	40.946209	0	0
26	Locked	40.946209	0	0
27	Locked	40.946209	0	0
28	Locked	40.366287	0	0
29	Locked	40.946209	0	0
30	Locked	40.366287	0	0
31	Locked	40.946209	0	0

[Gareth_L]

Hello siopoudis

We have just spoken on Twitter 

I am more than happy to take a look at this for you 
I will need to send you a private message to pass security 
If you can check the purple envelope top right of your screen that would be great 
Regards     
Gareth_L

[siopoudis]

Thanks Gareth,

I replied to your message

[Gareth_L · Accepted solution]

Thanks for those details siopoudis
I have booked the first engineer appointment we have available
You can check and reschedule this appointment through your online account if you need to
You can also cancel it if the fault has gone 
Can you please let me know how the visit goes 
Gareth_L

[siopoudis]

I appreciate it Gareth, I'll let you know how it goes.

[siopoudis]

Engineer just visited (it was actually the same who did the install 2 months ago, really helpful and knowledgable guy)

Checked in the house, no problems found. He was surprised that it was only getting 44mbps even with just Docsis 3.0 - he did say that with no Docsis 3.1 channel synced there is no way to get 1gig, but I should at least be getting around 600mbps which is the max for Docsis 3.0.
Then went to the green box and swapped my port to another one, speed is back to 1100mbps.

Engineer said port at the box was faulty and logged it.

Thanks for helping book the visit so quickly Gareth!

[jhuk]

I got 1Gb/s with no 3.1 channel and posted screens here, seems common for some areas fault to drop it but it was fixed for me same as when new it was random for weeks rarely hitting 1Gb/s then ok (I assume areas were not 100% ready for the sale of 1Gb/s yet).

It was random how much I got from less than 1MB/s to 940Mb/s but mainly 100-300Mb/s till the 3.1 channel came back.

Hint: issue was not in my home (the generic/default reply) and never has been in 24+years of being with VM.

The SamKnows is not accurate (if it can even find the HUB at times) look at my profile/photos and you can see single figures in an triple out then the exact opposite in next test.

[siopoudis]

Never had this, it always finds my Hub, unless after a reset which takes a while (and also makes sense).
I also test it with SpeedTest and Netgear's built-in speed test in the Wifi 6 mesh system I have installed, they always report similar speeds, and this was the case when it was faulty.

Sounds like my problem might have been different, as I never had "average" speeds, it was either 980 - 1100ish or the constant drop to 40-45mbps I had since Sunday until today that was fixed.

[Martin_N]

Thank you for keeping us updated on this siopoudis. 

We're glad to hear this is all resolved for you.

^Martin