cancel
Showing results for 
Search instead for 
Did you mean: 

1Gig install & Superhub 4 - now slower than before & no Docsis 3.1

gw0udm
Joining in

Hi all

I've recently had a self-install upgrade to 1 Gig fibre, having had the old M200 package for years.

According to speedtest.net I was getting at least 200MBit off it, even more perhaps. That was with a fairly old SuperHub 3 but it worked fine. The router is in an understairs cupboard at the end of quite a long piece of coax but it's always worked fine.

Since putting the SuperHub 4 the speed has dropped off a cliff - now I'm only getting 40MBit according to speedtest. I could see from the router dashboard that there were no Docsis 3.1 channels listed. I had a text from Virgin saying 'your services are now active' and after rebooting the modem I had a Docsis 3.1 channel and the speed jumped up to 700Mbit or so which to be honest I'd be quite happy with.

However this morning it's back down where it was yesterday and the 3.1 channel is missing again.

I've not tried customer services yet but thought it would be better to start here.

I'd be very grateful for any help!

Thanks

James

PS The odd thing is that no-one at home seems to have noticed... maybe I didn't need the upgrade after all 😉

15 REPLIES 15

gw0udm
Joining in

Here's the data from the hub:

Here's the data from the hub

3.0 Downstream channels

Channel

Frequency (Hz)

Power (dBmV)

SNR (dB)

Modulation

Channel ID

1

139000000

-3.400002

40.366287

QAM256

1

2

147000000

-4.299999

40.366287

QAM256

2

3

155000000

-4.799999

38.983261

QAM256

3

4

163000000

-5.500000

38.983261

QAM256

4

5

171000000

-5.799999

40.366287

QAM256

5

6

179000000

-6.500000

38.983261

QAM256

6

7

187000000

-7.000000

38.605377

QAM256

7

8

195000000

-7.599998

38.983261

QAM256

8

9

203000000

-8.200001

38.983261

QAM256

9

10

211000000

-8.400002

38.983261

QAM256

10

11

219000000

-8.900002

38.605377

QAM256

11

12

227000000

-9.099998

38.605377

QAM256

12

13

235000000

-9.500000

38.605377

QAM256

13

14

243000000

-10.000000

37.636276

QAM256

14

15

251000000

-9.900002

37.636276

QAM256

15

16

259000000

-9.799999

37.636276

QAM256

16

17

267000000

-9.799999

37.355988

QAM256

17

18

275000000

-10.000000

37.636276

QAM256

18

19

283000000

-10.599998

36.609653

QAM256

19

20

291000000

-10.299999

37.355988

QAM256

20

21

299000000

-10.799999

36.386890

QAM256

21

22

307000000

-11.599998

35.779911

QAM256

22

23

315000000

-12.099998

35.595078

QAM256

23

24

323000000

-13.099998

35.083549

QAM256

24

25

331000000

-13.000000

35.595078

QAM256

25

26

339000000

-13.299999

35.083549

QAM256

26

27

347000000

-13.799999

34.483570

QAM256

27

28

355000000

-13.900002

34.483570

QAM256

28

29

363000000

-14.599998

33.834164

QAM256

29

30

371000000

-14.400002

33.956509

QAM256

30

31

379000000

-14.400002

33.956509

QAM256

31

 

3.0 Downstream channels

Channel

Lock Status

RxMER (dB)

Pre RS Errors

Post RS Errors

1

Locked

40.366287

5

0

2

Locked

40.366287

0

0

3

Locked

38.983261

0

0

4

Locked

38.983261

0

0

5

Locked

40.366287

3

0

6

Locked

38.983261

0

0

7

Locked

38.605377

0

0

8

Locked

38.983261

0

0

9

Locked

38.983261

0

0

10

Locked

38.983261

6

0

11

Locked

38.605377

0

0

12

Locked

38.605377

0

0

13

Locked

38.605377

11

0

14

Locked

37.636276

0

0

15

Locked

37.636276

0

0

16

Locked

37.636276

0

0

17

Locked

37.355988

0

0

18

Locked

37.636276

0

0

19

Locked

36.609653

0

0

20

Locked

37.355988

0

0

21

Locked

36.386890

4

0

22

Locked

35.779911

14

0

23

Locked

35.595078

60

0

24

Locked

35.083549

311

0

25

Locked

35.595078

277

0

26

Locked

35.083549

1486

0

27

Locked

34.483570

2725

0

28

Locked

34.483570

1771

0

29

Locked

33.834164

9497

0

30

Locked

33.956509

4032

0

31

Locked

33.956509

2704

0

 

3.0 Upstream channels

Channel

Frequency (Hz)

Power (dBmV)

Symbol Rate (ksps)

Modulation

Channel ID

1

53700000

51.020599

5120 KSym/sec

64QAM

10

2

39400000

49.770599

5120 KSym/sec

64QAM

12

3

46200000

50.270599

5120 KSym/sec

64QAM

11

4

60300000

51.770599

5120 KSym/sec

64QAM

9

 

3.0 Upstream channels

Channel

Channel Type

T1 Timeouts

T2 Timeouts

T3 Timeouts

T4 Timeouts

1

US_TYPE_STDMA

0

0

0

0

2

US_TYPE_STDMA

0

0

0

0

3

US_TYPE_STDMA

0

0

0

0

4

US_TYPE_STDMA

0

0

0

0

-tony-
Alessandro Volta

downstream levels are way too low -6 is the minimum you want - upstream levels are just ok but they could do with looking at - you dont show any docsis 3.1 channels - there should be one

did the 3 have any attenuators on the input - if so have you moved them across - take them off if you have and see if that improves thing

if not you need a tech to sort things - wait here for VM or ring them

____________________

Tony.
Sacked VIP

Tudor
Very Insightful Person
Very Insightful Person

Very low downstream and high upstream which you have is often down to a cable fault. Just check that all coax connectors are tight.


Tudor
There are 10 types of people: those who understand binary and those who don't and F people out of 10 who do not understand hexadecimal c1a2a285948293859940d9a49385a2

Thanks all

There aren't an attenuators, but I have been round checking and cleaning all the connections. I did move to a different socket on one of the splitters too. One or two were a little loose.

Since doing that I now have a 3.1 channel again and much faster performance which is good, although the numbers on the box I'm seeing don't look that different... so maybe need an engineer to visit? I'm a little afraid they might condemn the internal wiring, it is the original VM wires but was tucked under the floor during building work some years ago so not easy to access now. It's worked great for years on the old modem to be fair.

Thanks again

James

Tudor
Very Insightful Person
Very Insightful Person

A good idea is to power off then on of the hub and after 1 hour of running post a new set of stats. This will show the current situation as some stats are accumulative.


Tudor
There are 10 types of people: those who understand binary and those who don't and F people out of 10 who do not understand hexadecimal c1a2a285948293859940d9a49385a2

Thanks, will do

So far the 3.1 channel is still there and Speedtest is showing about 800Mbps which I'm happy with although I suppose in theory it should be higher

James

Hi

Thanks all

Things seem a bit unreliable - through the course of the day the DOCSIS 3.1 channel seems to have come on and off, and the stats seem similar. Here are the latest although the 3.1 channel is up again now.

Is it now a question of getting someone out to have a look?

Thanks

James

3.0 Downstream channels

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

1139000000-2.50000040.946209QAM2561
2147000000-3.29999940.366287QAM2562
3155000000-3.90000240.366287QAM2563
4163000000-4.59999840.366287QAM2564
5171000000-4.90000240.946209QAM2565
6179000000-5.50000040.366287QAM2566
7187000000-6.09999838.983261QAM2567
8195000000-6.70000138.983261QAM2568
9203000000-7.20000138.605377QAM2569
10211000000-7.50000038.983261QAM25610
11219000000-7.79999938.605377QAM25611
12227000000-8.20000138.605377QAM25612
13235000000-8.50000038.605377QAM25613
14243000000-9.00000038.605377QAM25614
15251000000-9.09999837.636276QAM25615
16259000000-8.90000238.605377QAM25616
17267000000-9.20000138.605377QAM25617
18275000000-9.40000237.636276QAM25618
19283000000-9.79999937.355988QAM25619
20291000000-9.79999937.636276QAM25620
21299000000-10.00000036.609653QAM25621
22307000000-10.90000236.609653QAM25622
23315000000-11.59999836.386890QAM25623
24323000000-12.20000135.779911QAM25624
25331000000-12.50000035.779911QAM25625
26339000000-12.59999835.595078QAM25626
27347000000-13.00000035.083549QAM25627
28355000000-13.50000034.925610QAM25628
29363000000-14.00000034.483570QAM25629
30371000000-14.00000034.345688QAM25630
31379000000-14.20000134.345688QAM25631



3.0 Downstream channels

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

1Locked40.94620900
2Locked40.36628700
3Locked40.36628700
4Locked40.36628700
5Locked40.94620900
6Locked40.36628700
7Locked38.98326100
8Locked38.98326100
9Locked38.60537700
10Locked38.98326100
11Locked38.60537700
12Locked38.60537700
13Locked38.60537700
14Locked38.60537700
15Locked37.63627600
16Locked38.60537700
17Locked38.60537700
18Locked37.63627600
19Locked37.35598800
20Locked37.63627600
21Locked36.60965300
22Locked36.60965300
23Locked36.38689020
24Locked35.779911160
25Locked35.779911120
26Locked35.595078760
27Locked35.0835491800
28Locked34.9256102060
29Locked34.4835707440
30Locked34.3456886850
31Locked34.3456884760



3.1 Downstream channels

Channel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)
159964K1880QAM256759


3.1 Downstream channels

Channel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)
159Locked24-26.53465581011566

 

 

@gw0udm yes you need an engineer visit, although the 3.1 channel has decided to put in an appearance, the single level on it is so low, it might just well not bother!

The power levels on the rest of the downstream channels aren’t looking too healthy either.

Bottom line, there it either a bad connection or a damaged cable somewhere between the hub and the street cabinet.

Hi gw0udm, 

Thanks for your post and thanks for coming back to us in the Community. 

I'm sorry to hear that you've been having an issue with your services and speed. Checking things this end, it does look as thought the levels could do with some adjusting. We won't be able to fix this remotely so I would like to arrange for an engineer to come to take a look at this for you. 

I just need to confirm the address to ensure we are booking the visit on the correct account. I have sent you a private message regarding this. Just click on the little plum envelope at the top right-hand side of the page to access your inbox.

Thanks,

Kath_F
Forum Team

New around here? Check out the do's and don'ts, in our Community FAQs