1gb with Hub 4 modem only mode.
 

Are there any known issues with Hub 4 operating in modem only mode?

Family member had M350 which was always rock solid around the 380 DL speed and upgraded to 1Gb service, speeds now are fluctuating wildly between 300-500mbps. The only thing that's changed apart from level of service is the SH3 was replaced for a SH4. Router (AX6100) etc all remains the same.

Swapped cables etc. but no joy

Thanks in advance.

EDIT: Here's the downstream (i have no idea how to interpret this....)

3.0 Downstream channels
Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
25 331000000 3.3 37.6 QAM256 25
1 139000000 6.4 39 QAM256 1
2 147000000 6.7 38.6 QAM256 2
3 155000000 7.5 39 QAM256 3
4 163000000 7.2 39 QAM256 4
5 171000000 7 39 QAM256 5
6 179000000 7 38.6 QAM256 6
7 187000000 6.8 39 QAM256 7
8 195000000 6.6 39 QAM256 8
9 203000000 6.6 39 QAM256 9
10 211000000 6.7 38.6 QAM256 10
11 219000000 6.7 39 QAM256 11
12 227000000 6.6 39 QAM256 12
13 235000000 6.5 38.6 QAM256 13
14 243000000 6.5 39 QAM256 14
15 251000000 6.3 39 QAM256 15
16 259000000 6.2 38.6 QAM256 16
17 267000000 5.9 38.6 QAM256 17
18 275000000 5.5 39 QAM256 18
19 283000000 5 38.6 QAM256 19
20 291000000 4.5 38.6 QAM256 20
21 299000000 4.4 38.6 QAM256 21
22 307000000 5 39 QAM256 22
23 315000000 5 39 QAM256 23
24 323000000 4.4 38.6 QAM256 24
26 339000000 0.1 36.6 QAM256 26
27 347000000 1.5 37.4 QAM256 27
28 355000000 3.9 37.6 QAM256 28
29 363000000 4.7 38.6 QAM256 29
30 371000000 4.9 39 QAM256 30
31 379000000 5.1 38.6 QAM256 31


3.0 Downstream channels
Channel Lock Status RxMER (dB) Pre RS Errors Post RS Errors
25 Locked 37.636276 0 0
1 Locked 38.983261 0 0
2 Locked 38.605377 0 0
3 Locked 38.983261 0 0
4 Locked 38.983261 0 0
5 Locked 38.983261 0 0
6 Locked 38.605377 0 0
7 Locked 38.983261 0 0
8 Locked 38.983261 0 0
9 Locked 38.983261 0 0
10 Locked 38.605377 0 0
11 Locked 38.983261 0 0
12 Locked 38.983261 0 0
13 Locked 38.605377 0 0
14 Locked 38.983261 0 0
15 Locked 38.983261 0 0
16 Locked 38.605377 0 0
17 Locked 38.605377 0 0
18 Locked 38.983261 0 0
19 Locked 38.605377 0 0
20 Locked 38.605377 0 0
21 Locked 38.605377 0 0
22 Locked 38.983261 0 0
23 Locked 38.983261 0 0
24 Locked 38.605377 0 0
26 Locked 36.609653 0 0
27 Locked 37.355988 0 0
28 Locked 37.636276 0 0
29 Locked 38.605377 0 0
30 Locked 38.983261 0 0
31 Locked 38.605377 0 0


3.1 Downstream channels
Channel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)
39 96 4K 1880 QAM4096 424


3.1 Downstream channels
Channel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)
39 Locked 40 5 858803578 0

Re: 1gb with Hub 4 modem only mode.
 

Those power levels are fine. From what I can find the AX92u has a wan to lan throughput of around 940mbits which is the same as my router.

I too have upgraded to 1gbit and I also was given a shub 4. I haven't had a problem with speed tests because the best server to run speed tests on is also geographically the closest to me and so coincidentally was first on the list to use.

Which brings me to my first point. How are you doing your speed tests. I have always used speedtest.net for mine and whilst I have always found it very reliable for all previous tiers of 500mbits and below I have found through a lot of experimenting that there are only two servers for me which can provided consistent results for 1gbit so you might want to try a few different servers.

If that doesn't bear fruit the next best solution to immediately ascertain what the problem is is to put the shub back in router mode and use the built in samknows speed test to do a test. It runs the test straight to router and if you get full speed you know the problem is on the lan side and if you still only get ~500mbits then it is nothing to do with you and a problem VM's side. I hate ro recommend putting the shub back in router mode because I have always had all my shubs in modem mode but on this occasion it is quickest and easiest way to drastically reduce the list of things to troubleshoot.

When in router mode all you need to do is open your web browser and type in

samknows.com/realspeed

Re: 1gb with Hub 4 modem only mode.
 

General, thanks for your comments.

To answer your q's

1. I am indeed using speedtest.net, it's built into the A92u interface
2. I've put the CM back into router mode & used the samknows tool i can see the speeds getting to the router are expected but with two laptops freshly rebuilt (one mac & one win) both connected via ethernet i'm seeing the same issue.

Re: 1gb with Hub 4 modem only mode.
 

there in lies the problem. VM are giving you full speed to the shub and it is either the cables, switches or nics after that that are causing your issues. It is a shame you haven't got a pc you can run a wired test on. Laptops are always flaky performance wise due to resource and power management and either the nics are the bottleneck in terms of straight forward throughput (e.g. can only handle 400mbits) or the cpu (which the nic relies on to process data) can't keep up with that speed due to resource sharing and thus the cpu or ram are a bottleneck for network performance.

You say they are rebuilt but if they are branded laptops it might be worth googling them to see if you can find any reviews or articles where people have commented on what kind of throughput you can expect. I'll be honest and say if I bought a laptop, unless it was £2000 with an ssd and top notch everything, I wouldn't expect to be able to download over 100MB/sec.

Re: 1gb with Hub 4 modem only mode.
 

Borrowed & Had both machines on wired and wireless at my work both near as dammit pulling 1gb over their respective connections.

It’s not the machines, it’s not the AX92u I’ve tried wan port aggregation and I’m still seeing poor performance, it’s something on the hub

Re: 1gb with Hub 4 modem only mode.
 

Yep it’s a piece of crap.

Re: 1gb with Hub 4 modem only mode.
 

If I was in your situation my next step would be to put the shub in router mode and directly connect the laptops to the shub and run the speed test again. If you get full speed you know it isn't the shub which is the issue and it is the Asus router or something else. If you still have a problem then it is a factory reset and fingers crossed and when that doesn't work it is ringing up tech support and trying to wangle another shub out of them. The problem is that even if you get through to second line they'll get you to run the samknows speed test and when that comes back at full speed they'll say the shub isn't at fault.

Re: 1gb with Hub 4 modem only mode.
 

Put it into router mode, connected the same devices via Ethernet to the shub (one at a time) same result.

Sam knows shows expected speeds to the hub but again only 300-500 over Ethernet to endpoints.

Factory reset the hub tried again, same thing

Re: 1gb with Hub 4 modem only mode.
 

Imho the next step would be to try a different hub but trying to persuade tech support to give you a new one when they can prove you are getting full speed is going to be a big ask. Have you got a friend or neighbour you could pop into for 5 mins at some point and try it on their connection?

Re: 1gb with Hub 4 modem only mode.
 

I have read the conversation above and agree that General's assessment and steps are sound.

One thing occurs to me though. Last time I could get no more than 300-500Mb on my 1Gbs connection, with Hub 4 in modem-only mode, the problem was that I had my AX11000 QoS enabled. The effect of this was to ensure that none of my devices could get more than approximately 500Mb so that no device, game system etc could hog the bandwidth. QoS is unnecessary with 1Gb connection, because it is really only designed for those with limited bandwidth to share out. If you have enabled QoS or it is enabled by default, that could be your problem.

Re: 1gb with Hub 4 modem only mode.
 

I have found the SamKnows speedtest maxes out the CPU on my old laptop but is fine on my desktop. Have you tried looking at the CPU usage in task manager and shutting all running software down to see if it improves the results?

Re: 1gb with Hub 4 modem only mode.
 

Enabling QoS on my Netgear always killed downloads speeds.

Re: 1gb with Hub 4 modem only mode.
 

I was going to post in the other 1 gig forum post, I have the same issue, using the hub 4 and my unifi gear I get terrible download speed, speedtest has the download speed at 537 Mbps.

Put the Hub4 back to router mode and use the samknows still get terrible speed 432 Mbps that is directly connected from the PC to the hub with a new cable.

Re: 1gb with Hub 4 modem only mode.
 

Your issue is different to the ops because he is getting full speed to the hub. You aren't are your issue is with VM.

Re: 1gb with Hub 4 modem only mode.
 

Do you still have the problem? A fix for slow speeds on some Hub4s was deployed on Saturday.

If you do still have the problem, try a factory reset on the Hub.
https://www.virginmedia.com/help/vir...reset-your-hub

Re: 1gb with Hub 4 modem only mode.
 

---------- Post added at 13:03 ---------- Previous post was at 13:02 ----------

Just done a factory reset still have the same issue.

Re: 1gb with Hub 4 modem only mode.
 

agreed. i had issues with slow speeds to the hub using samknows speed test. VM put in a new cable run from the cabinet for me. now getting a solid 1154 to the hub but unfortunately only 950 to the PC.

---------- Post added at 13:34 ---------- Previous post was at 13:31 ----------

thats a cabling issue my friend. something not right with your network. if youre using a gigabit network you should be seeing nearly 950 with a wired connection. WiFi speeds will vary alot.

Re: 1gb with Hub 4 modem only mode.
 

I think it's more of a Hub 4 issue than my cabling, 3 different cat 6 cables used. Even used a cat 5e cable to test same result slow speed from the hub 4 to the PC

Re: 1gb with Hub 4 modem only mode.
 

The PC speed on the right will be affected by processor issues etc. in the PC as you are using a browser.

Try Ookla speedtest app for PC download speed.

I get between 400-800Mbs to the PC in Edge but 1.1Gpbs you the Hub4. Ookla usually gives 900+Mbs.

Re: 1gb with Hub 4 modem only mode.
 

I think I have a similar issue to the OP. I have a new SH4 in modem mode connected to an Eero mesh router. The router reports a connection to the Internet of c.1Gb but my devices are only showing 600Mb connections.
Mr Spiderplant - will a factory reset resolve this? I’m confused as you say the fix is only for “some” SH4s

Re: 1gb with Hub 4 modem only mode.
 

Oh ok. Chances of 3 cables being dud are remote.

Re: 1gb with Hub 4 modem only mode.
 

There was a fault where some SH4s wouldn't use all the downstream channels so they couldn't get the full 1Gbps. Instead they'd get a very consistent lower speed such as 380Mbps. A fix was deployed for this on Saturday, but there is some speculation that a factory reset may also be necessary. This is the fault I thought j0s0r had. However now they have posted SamKnows data showing they are getting 1145Mbps at the hub, that clearly isn't the problem. As others have said, j0s0r's problem is somewhere on the LAN side, and it sounds like your is too.

No harm in trying a factory reset though.

---------- Post added at 19:28 ---------- Previous post was at 19:24 ----------

Don't rule it out, if they all came from the same source. I once had a box of 100 and they were all dud (the wrong pairs were twisted)

Re: 1gb with Hub 4 modem only mode.
 

Actually i read it as the same issue as mine

Full speed to the hub, but Ethernet hand off from hub to device is very poor.

My two laptops connected (one Mac and one windows) each connected via Ethernet and done one at a time to the SH4 with no wireless devices receive between 300-500

The router does exactly the same.

The same machines and cables connected to a work iot network receive near enough 1gb

The above proves that it’s not the cable or device NIC causing the issue.

Re: 1gb with Hub 4 modem only mode.
 

it's not

Re: 1gb with Hub 4 modem only mode.
 

Considering Samknows gives two speeds It’s open to interpretation as it doesn’t specify if that speed is to the hub or the device. I believe it’s the latter.

Regardless, my issue for is not with router, devices or cabling. I now somehow need vm support to appreciate this.

Re: 1gb with Hub 4 modem only mode.
 

Try windows safemode with networking and see what speed you get. I did it this morning and I am getting the full proper speed

So done a reset of windows and everything seems sorted

Re: 1gb with Hub 4 modem only mode.
 

Thanks, but as i've already said, the same equipment connected on another network gives near enough 1gb speeds. the laptops & cables are sound, the issue is with the handoff from the SH4

Re: 1gb with Hub 4 modem only mode.
 

Did the potential router issue get considered in your case MrM. You didn't tell us what router you have and whether or not QoS is enabled.

Re: 1gb with Hub 4 modem only mode.
 

It did, QOS disabled and still the same issue.

Also PIN reset the SH4 this morning, repeated testing with both laptops and router as before, same issue.

Re: 1gb with Hub 4 modem only mode.
 

Somewhere in the forum someone said that the Hub 4 was replaced and this went away. I can't pinpoint it. Is it time to put a call in?

Re: 1gb with Hub 4 modem only mode.
 

:confused:

Re: 1gb with Hub 4 modem only mode.
 

After an hour on the phone to VM on Saturday during which time they wanted me to leave the SH4 in router mode for three days (which I flatly refused) there’s an engineer coming out on Monday, hopefully the problem will be resolved

Re: 1gb with Hub 4 modem only mode.
 

I wouldn't hold your breath. He is going to do the samknows speed test, check all the power levels and say everything is fine. He hasn't got the time or training to start swapping about bits of customer equipment and ascertain where the problem lies. The best you can hope for (and I hope it works) is that he swaps the shub over and it cures the problem.

Re: 1gb with Hub 4 modem only mode.
 

@General Maximus, read something, somewhere earlier today, that suggests the white cable feeding into the SH isn't rated for 1gbps and it should be black? is that correct? I've a feeling it's a) not relevant & b) nonsense. would be good if someone in the know could confirm?

Re: 1gb with Hub 4 modem only mode.
 

Absolute flipping rubbish. It is standard coax (rg6 rings a bell) and is certified to transmit at however many gigabits per second.

Re: 1gb with Hub 4 modem only mode.
 

Had a feeling that was the case, thank you for confirming....

So, an update on todays engineer visit.

First of all the tech was very good indeed and it appears i have or have had two problems. First of all i replicated the fault in fron of the tech. showed him the issue in both router and modem mode.

we replace the SH4 connect my mac via ethernet and bang straight away maximum speed. this is good....

Next, we put my kit back on, speed test via my router back to the same problem again.

I then spoof the MAC of my mac's ethernet adapter, reboot all the kit. connect up via ethernet into my home router again with a different adapter. bang, maximum speed...

oddness.....