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TeaParty
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Inconsistent speed Gig1 DA7 area

Over the past couple of days we've had really inconsistent speed on our Gig1 connection.

Speed is usually over 1000 to the hub on samknows/realspeed but it's been as low as 10mbps over the past couple of days.

I've just done a test which has come up as 232mbps

Screenshot 2021-06-28 at 21.21.37.png

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TeaParty
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Re: Inconsistent speed Gig1 DA7 area

3.0 Downstream channels

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

253307500001.40000238.605377QAM25625
11387500001.79999934.483570QAM2561
21467500002.50000034.925610QAM2562
31547500002.59999836.386890QAM2563
41627500002.70000137.355988QAM2564
51707500002.59999837.636276QAM2565
61787500002.50000037.636276QAM2566
71867500002.50000037.636276QAM2567
81947500002.50000037.355988QAM2568
92027500002.50000037.355988QAM2569
102107500002.29999937.355988QAM25610
112187500002.70000136.386890QAM25611
122267500002.79999937.355988QAM25612
132347500002.59999837.636276QAM25613
142427500003.00000038.605377QAM25614
152507500002.70000137.636276QAM25615
162587500002.40000237.636276QAM25616
172667500002.40000237.636276QAM25617
182747500002.59999838.605377QAM25618
192827500002.40000237.636276QAM25619
202907500002.20000138.605377QAM25620
212987500002.40000237.355988QAM25621
223067500002.40000238.605377QAM25622
233147500002.09999837.636276QAM25623
243227500001.40000237.636276QAM25624
263387500000.90000237.636276QAM25626
273467500000.00000037.636276QAM25627
28354750000-0.29999937.636276QAM25628
29362750000-0.79999937.636276QAM25629
30370750000-1.20000137.355988QAM25630
31378750000-1.70000137.355988QAM25631



3.0 Downstream channels

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

25Locked38.605377200
1Locked34.4835701697644730184
2Locked34.9256101742759218484
3Locked36.38689024329820
4Locked37.3559881020
5Locked37.636276189820
6Locked37.636276676260
7Locked37.636276160
8Locked37.355988370
9Locked37.355988550
10Locked37.355988850
11Locked36.3868901080
12Locked37.355988391
13Locked37.636276310
14Locked38.605377240
15Locked37.636276330
16Locked37.636276270
17Locked37.636276270
18Locked38.605377200
19Locked37.636276200
20Locked38.605377120
21Locked37.355988120
22Locked38.605377220
23Locked37.636276250
24Locked37.636276290
26Locked37.636276140
27Locked37.636276140
28Locked37.636276140
29Locked37.63627690
30Locked37.35598880
31Locked37.35598870



3.1 Downstream channelsChannel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)
33944K1840QAM4096424


3.1 Downstream channelsChannel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)
33Locked39-3.177201032713
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TeaParty
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Re: Inconsistent speed Gig1 DA7 area

3.0 Upstream channels

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

12580000046.5205995120 KSym/sec64QAM4
24620000044.2705995120 KSym/sec64QAM1
33940000045.0205995120 KSym/sec64QAM2
43260000045.7705995120 KSym/sec64QAM3



3.0 Upstream channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1US_TYPE_STDMA0020
2US_TYPE_STDMA0000
3US_TYPE_STDMA0000
4US_TYPE_STDMA0000

 

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Andrew-G
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Re: Inconsistent speed Gig1 DA7 area

Looks like a problem around 140 MHz, probably noise ingress.  The source of the 140 Mhz signal could be a range of things - equipment fault with VM, or assorted permitted private mobile radio use, satellite communication, military and public sector uses.  If it's external signals, they can't be stopped, but if VM can find the faulty shielding/ingress point or equipment fault that can be fixed.    

A point of noise ingress is usually easily addressable, although if it is intermittent then the field technicians may struggle to observe the fault, and you then might get the "looks good from our side" answer.  As VM don't use advanced tools to locate noise faults outcomes are a bit of a mixed bag - many are found and fixed easily, a very, very few are never found and never fixed.

You should check that the connections of the coax cable between hub and wall are properly made and finger tight (ideally undo them and redo them, though that'll knock the hub offline for 5-7 minutes), and if you've got any splitters or TV boxes with unused ports or unused VM coax spurs then check they're fitted with a terminator cap.  A reboot, or interrupting the coax may well briefly restore performance because the hub initially re-negotiates a full set of channels, but that won't address any noise ingress issue, so it will then recur as the hub changes frequency "on the fly".

I'll mark your post for the forum staff to advise.  If you phone it in, probable outcome is that the offshore script readers will tell you to reboot the hub, it'll initially work fine, and they'll tell you that's fixed, even when the actual problem is not fixed at all.

I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more

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John_GS
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Re: Inconsistent speed Gig1 DA7 area

Hi TeaParty

 

Thanks for posting and welcome to the community.

 

My apologies for the broadband issues. 

 

I've checked the system today and no issues are showing, so I did a deeper check, all the levels are fine for SNR (signal to noise ratio), power levels and congestion levels etc.

 

I can see you've literally rebooted the hub, so please monitor the connection for me and report back any issues. Best,

John_GS
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TeaParty
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Re: Inconsistent speed Gig1 DA7 area

Andrew-G many thanks for having a look at it for me.

John_GS thank you too.

I read Andrew-G's post this morning, checked the cables were all tight and tried to do another Samknows/Realspeed test.

However it was stating that my hub was offline (it wasn't as I had internet connectivity)

So I rebooted the hub and then the speed test worked.

As of now I'm getting 1047mbps to the hub. I reboot the hub once per day or so when I notice connectivity or speed issues. General day to day use for browsing / streaming etc seems fine but if I do a big download from Xbox or PSN stores it really shows.

But again, thank you both for your replies and I'll keep an eye on it.

 

Screenshot 2021-06-29 at 08.48.58.png

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John_GS
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Re: Inconsistent speed Gig1 DA7 area

You're more than welcome 🙂 do keep us posted

 

Best,

John_GS
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