BT Digital Voice and huge drop in upload speed sync on route

Hi Guys,
On the 21st November I was moved over to BT Digital Voice.
I did not mind moving over to BT Digital Voice, and to be honest I have been waitnig for my turn to come. Even spashed out on two of their cordless handsets that connected to the Smart Hub 2.
I was posted a new Router (Smart Hub 2) as my old BT Router did not support VOIP!
Not a problem again.
I changed over the router (Smart Hub 2) the night before the move to Digital Voice.
By the next day (21st) my upload speed went from a solid 20Mbs (Well slightly less by the looks of it ) right down to a 11Mbs
I thought OK there has been an update on the contract because of BT Digital Voice, so maybe the line has been reset and need to wait the 10 days for the retraining of the VDSL line. But still on the 10th day and beyond no chnage. I have not been rebooting my router all the time to see if it will connect at a better uplaod speed as I know if you keep doing that the greenbox in the street thinks there might be an issue and reduce the speed.
On the 21st when Digital Voice became live. I checked the old analogue phone and there was a dial tone in the morning, but in the afternoon there was nothing. Totally cut. And looking at the stats that is roughtly the time the upload speed on my line dropped! Could there be anything related to this, as the cut was probably done at the exchange and not the green cabinet in the street.
Below are the stats from the new Smart Hub 2.
Tomorrow Im going to experiment. Im going to re connect my old router and leave it a day and see hat happens. Yer I know I will be without Digital Voice.
Can anyone think what else might have caused this massive drop in upload speed?
I called BT today and they were not interested in sending an engineer to investigate/fix the upload speed issue. There is only a download speed guarantee!
Eventually after been persistent they have booked an engineer! But as above if anyone knows what it might be please help !
My downlaod speed has not been affected at all.

ROUTER STATS
12:16:04, 20 Nov.
DSL Link Up: Down Rate=79999kbps, Up Rate=18399kbps; SNR Margin Down=3.6dB, Up=6.0dB
01:16:15, 21 Nov.
DSL Link Up: Down Rate=79999kbps, Up Rate=18256kbps; SNR Margin Down=3.7dB, Up=6.0dB
15:34:40, 21 Nov.
DSL Link Up: Down Rate=79999kbps, Up Rate=11681kbps; SNR Margin Down=3.7dB, Up=6.1dB
01:42:51, 23 Nov.
DSL Link Up: Down Rate=79999kbps, Up Rate=11998kbps; SNR Margin Down=3.9dB, Up=6.1dB
03:48:09, 23 Nov.
DSL Link Up: Down Rate=79999kbps, Up Rate=12118kbps; SNR Margin Down=3.9dB, Up=6.1dB
16:47:31, 30 Nov.
DSL Link Up: Down Rate=79999kbps, Up Rate=11532kbps; SNR Margin Down=3.5dB, Up=6.1dB
18:19:36, 05 Dec.
DSL Link Up: Down Rate=79999kbps, Up Rate=11995kbps; SNR Margin Down=4.1dB, Up=6.1dB
18:37:55, 09 Dec.
DSL Link Up: Down Rate=79999kbps, Up Rate=12002kbps; SNR Margin Down=3.8dB, Up=6.1dB
13:08:19, 16 Dec.
DSL Link Up: Down Rate=79999kbps, Up Rate=11883kbps; SNR Margin Down=3.4dB, Up=6.1dB

Thanks
Simon

First thing I’d try is putting the old router back on and see if this produces a better upload sync rate.

It is possible that you have had cab work done, and the new port is the cause maybe ?

The ceases of dial tone from the exchange don’t happen that quickly.

Strange the noise margin for both up and down didn't change when you switched to VOIP although the upload speed did, that doesn't seem right to me.

In reply to a post by Zarjaz:

It is possible that you have had cab work done, and the new port is the cause maybe ?

How likely would this be?

It's possible. Apparently Openreach will be doing compression work in some cabs to free up line cards for spares.

Hi
I've had the same. We were getting up to 70mbps and experiencing that as well. At the point of cut over to Digital Voice the potential has been halved and the real speeds we are seeing are sitting at 20mbps. Yes there is likely to be a technical fault on the line but that doesn't explain how BT knew the potential speed drop was going to be this dramatic.
The documentation about the move to Digital Voice states that it won't have a noticable impact on your Broadband Speeds.
I was just fed a line about age of copper wiring being the limiting factor. I wonder if they are trying to squeeze more customers onto the same equipment.
This doesn't feel right at all.
Rob

The addition of Digital Voice to a line will have no effect on Download or Upload sync speeds, and a minimal effect on data throughput speeds when a VOIP call is in progress.

There is no dramatic potential speed drop so there must be other reasons for the change in speed.

Report a speed fault to support.

Edited by Realalemadrid (Thu 21-Dec-23 15:45:32)

I have reported a speed fault but the main problem is that BT have used the migration to force us onto a lower grade service. They have halved the potential of the service and are talking about reducing the price by only 15%. They are still charging us the full £49 pm at the moment. They are not giving us any options and have done this to at least one other neighbour. I spoke to another broadband provider today and they will migrate us back onto an 70Mbps potential circuit in 10days in the same exchange but we lose our telephone number. BTs approach and behaviour with this is appalling.

Edited by rslatem (Fri 22-Dec-23 20:54:04)

In reply to a post by SimonInReading:

Hi Guys,
On the 21st November I was moved over to BT Digital Voice.
I did not mind moving over to BT Digital Voice, and to be honest I have been waitnig for my turn to come. Even spashed out on two of their cordless handsets that connected to the Smart Hub 2.
I was posted a new Router (Smart Hub 2) as my old BT Router did not support VOIP!
Not a problem again.
I changed over the router (Smart Hub 2) the night before the move to Digital Voice.
By the next day (21st) my upload speed went from a solid 20Mbs (Well slightly less by the looks of it ) right down to a 11Mbs
I thought OK there has been an update on the contract because of BT Digital Voice, so maybe the line has been reset and need to wait the 10 days for the retraining of the VDSL line. But still on the 10th day and beyond no chnage. I have not been rebooting my router all the time to see if it will connect at a better uplaod speed as I know if you keep doing that the greenbox in the street thinks there might be an issue and reduce the speed.
On the 21st when Digital Voice became live. I checked the old analogue phone and there was a dial tone in the morning, but in the afternoon there was nothing. Totally cut. And looking at the stats that is roughtly the time the upload speed on my line dropped! Could there be anything related to this, as the cut was probably done at the exchange and not the green cabinet in the street.
Below are the stats from the new Smart Hub 2.

Thanks
Simon

This may be a coincidence that migrating to DV caused loss of upload speed. I'm on FTTC DV voice service and I do not really see any loss of upload speed.

Data rate:19.221 Mbps / 79.757 Mbps
Maximum data rate:19.221 Mbps / 82.046 Mbps

For me getting 19.2 Mbps is the lowest I get with BT FTTC. Most of the times it is synced at 20Mbps. One of the cause is recent firmware update of the Smart Hub 2 router and router can re-sync sometimes lower or higher. There were also some occasions when after 14 days Smart Hub 2 router is programmed to reboot causing a changes in sync speeds but this should also stop doing that eventually.

My upload speeds have been that way for 2 years now even shortly before switching to BT from TalkTalk. It may be slight impact of crosstalk.

However, if you continue to turn your router on and off this will trigger DLM to reduce your speeds. You have to leave it alone and it should correct itself over time.

I personally don't see any reason why DV should cause a reduction in upload particularly if you have the Digital handset switched off. You can make an experiment to unregister the handset and if you have any existing old telephone connected to the router, unplug it and see if that solves the issue but I doubt this has anything to do with it.

Regarding the dial tone, it is completely normal to have no dial tone on the old analogue phone when plugged into the master socket! This is not a defect. I have mentioned it on many posts previously. When you switch to Digital Voice your analogue line gets turned off meaning if you were to connect a phone into the Faceplate socket telephone port it will not get any dial tone any more!

In essence what we are getting now under Digital Voice is SOGEA (Single Order Generic Ethernet Access) without analogue phone service. VOIP is simply included as part of this switch and from now on you can only connect your phone to the router.

Whether or not the digital handset is on or off will make ZERO difference to the sync speed. This is the raw data rate between the chipset in the router and the chipset in the DSLAM in the cabinet.

The obvious thing that *has* changed here is the router itself. Try putting back the old router and see if the upload speed is better.

Otherwise, it's *possible* that in the process of reprovisioning you as SOGEA, you have been moved to another port in the cabinet. But that's fairly unlikely, as they'll want to avoid engineer visits for this sort of stuff.

Yes, I'm aware it will not make any difference to the sync speed. But I'm suggesting this to the OP to clear any misconceptions or the placebo effect that he may have. Maybe it is just psychological that the OP thinks Digital Voice is causing a dip in his upload. The most likely scenario is the migration from his old provider to the new one that is the reason and the line is trying to find a stable connection.

I don't think DV can affect the speed itself because the router is still supposed to sync at the highest upload sync speed that the line will allow. One thing is the sync speed being low and the other thing is a sync speed being high but bandwidth being stolen causing speed reduction.

Clearly, OP is saying that his sync speed dropped to Up Rate=11883kbps. That is simply the router being synced at a lower speed. Digital Voice has no negative bearing on this.

The Smart Hub 2 Firmware updated: 13-Dec-2023 ten days ago. Router then reboots causing difference in sync speeds. It might be that the OP kept rebooting his router too frequently to try and fix it and instead that made his upload speed drop further as DLM was interpreting his line as instable.

Out of interest, are any physical changes made to the line when moving to DV?

Does the exchange line side connection to the cabinet get disconnected?
If so could something have gone wrong there?

No, the E-side remains connected to the exchange for regular automated line tests. In most cases the battery voltage is no longer applied to the line, and at some point the ties between the TAM and PSTN equipment may be removed (these would no longer be installed for a new SOGEA circuit).

Absolutely no changes. There are no engineer visits. However, in some rare cases an engineer might come only to install an NTE5c MK4 Faceplate socket. That's what I had when I first joined TalkTalk FTTC 3 years ago.

But no change when migrating to BT FTTC. The problem is not much clarity is given to the customers. All you get told is that you are migrating to Digital Voice and to plug telephone into the router. You get an alexa handset phone that you need to register once by pressing WPS button on router while the handset is on and must be charged.

But no one explains that plugging a telephone into the Faceplate socket will not return any dial tone. This may cause confusion for some people especially if they get installed the NTE5c MK4 Faceplate as the telephone port will not work as analogue is turned off.

Hey Guys,

OK BT sent a person, not an engineer, but a person that helps set ups. I was well annoyed and this person could see it. He confirmed that the uload speed was slower than expected considering this happed within hours of moving to DigitalVoice.

So did quite a bit of looking online and found an Australian had a similar issue.

Once a twisted pair (cable that goes to your house) has its woltage turned off the cable is more suspectable to "echos" (his words), and if you have Bridge Taps in place the issue can be horrendous.
Well I do have two extension cables coming from the Master socket. One to the sitting room and the other to the upstaors room where the router is.

So took the router down to the master socket and plugged it into the test socket wich disconnects all other cabling in the house.

And BOOOM! conected at max up and download speed. I see the Upload dB went right up (dont know if that is an issue)

10:11:38, 25 Dec.
DSL Link Up: Down Rate=79524kbps, Up Rate=13220kbps; SNR Margin Down=4.3dB, Up=6.1dB
15:00:57, 28 Dec.
DSL Link Up: Down Rate=79999kbps, Up Rate=20000kbps; SNR Margin Down=4.7dB, Up=10.1dB

So now I have the router on the hall floor and connected to a Ethernet over power adapter to get the internet back upstairs to where my office is.

Now my question before I do it. Yes there was a T on the home wiring and now no voltage on the line this causes an issue. If I reconnect a single connection up to the office would that be affected by this so falled "echo" or not an issue since a single connection extension?

Just a shame this is not more promoted to disconnect any redundant internal home cabling when moving to Digital Voice. Maybe guys here at Think Broadband can do an article on it to make peole aware and the Physics behind it why it happens

The higher SNR on uplink is not an issue. In fact it's a good sign; when the link is running at 20Mbps there is a big signal-to-noise ratio (i.e. very little noise), so the link is likely to be rock solid.

For the extension wiring, do you mean that you want to plug in analogue phones? If so, you should connect the extension wiring directly to the voice port on the router. It won't make any difference at all to the data speed, since that's a completely separate connection.

Or are you saying you want to move the router back to where it was before, using the extension wiring to connect the router to the master socket, with no extension phones? In that case, you may have to unpick your wiring a bit so that only the minimum amount of cabling is used, in a straight line without a "T", and you must ensure that this "extension" wire (which is really just carrying data) is connected to the correct point inside the master socket. That is: in a modern master socket, I think you'll find there's one connection point for voice extensions, and a different one to extend the data connection to a router which is away from the master socket. Any joins between cables should be kept short and don't untwist the cabling.

The advantage of moving the router back is that you can dispense with the ethernet-over-power adapter, which may not be very reliable.

Reconnect a single extension and you will be fine. Just the two wires in a single pair (I think blue is pair 1) to pins 2 and 5 on the rear of the removable faceplate part of the master socket, then check they are the same at your upstairs room. Leave the sitting room wire disconnected.

Just a shame this is not more promoted to disconnect any redundant internal home cabling when moving to Digital Voice. Maybe guys here at Think Broadband can do an article on it to make peole aware and the Physics behind it why it happens

To be fair, this information is widely available, and has been for many, many years.

Losing the dial tone from exchange equipment DOES NOT make the pair more susceptible to external signals.

My upload and download speeds are finally up to the max on my end as well!

I think, what we can also attribute to the speed differences is crosstalk!

Data rate:19.999 Mbps / 79.999 Mbps
Maximum data rate:21.999 Mbps / 80.881 Mbps
Full Fibre (FTTP) Mode:Off
Noise margin:5.4 / 3.0
Line attenuation:10.6 / 16.8

For the first time since being a BT customer for 1 year and 6 months (18 Jul 2022) I am getting the full 80/20Mbps never seen before since TalkTalk!

Upload speed wasn't really an issue however, it did dip sometimes to 18Mbps. The real experience is the fact that I wasn't getting 80Mbps Data rate even though with TalkTalk for several months I had no issue syncing at max speeds. With BT it has mostly been averaging 77-78Mbps and I was always wondering why. While upload was averaging 19Mbps.

Community Fibre became available in my building in December 2022. I believe over the last month in my building 4 customers switched to Community Fibre and that has made my FTTC speeds go back to 80/20Mbps!

Here's what I've been looking at! I live in a building with 82 flats of, which 19 customers have switched to the new Community Fibre FTTP service.
Community Fibre take-up Flats: 4, 5, 7, 8, 40, 45, 46, 43, 44, 45, 46, 51, 53, 58, 59, 73, 76, 77, 79. I checked each flat one by one out of curiosity to see how many of them have switched to the new service.

Last month when I checked there were 15 customer take-up. So it seems that those 4 extra customers that have now switched to FTTP meant that now I am syncing at the full speed! This is certainly not a coincidence.

Though, another observation, I have been moved to a different FTTC cabinet that is closer to my property! I did not mention this before. But for the last few months, I was with "........BISHOPSGATE is served by Cabinet 20" and that has now changed to ".........BISHOPSGATE is served by Cabinet 7"

The newer cabinet 7 is in Wentworth Street, while my old cabinet 20 was in Old Montague Street here in Central London. I have no idea how Openreach decided to move my FTTC cabinet! This is definitely something that is quite rare and unusual.

Nevertheless, initially this did not really make much of a difference to my speeds. Because with my old cabinet 20 in Old Montague Street, I was also syncing 80/20 before crosstalk became a factor several months later. Then I got moved to the closer cabinet 7 in Wentworth Street that's 0.1 mile (around 160 meters) closer to my home it didn't make much difference until now.

Perhaps crosstalk is the bigger factor that impacts both upload and download speeds. The more the customers from an FTTC cabinet move onto to FTTP the higher the FTTC speeds will naturally become over time. I always suspected that this was naturally going to happen and now it is proving to become a reality.

My FTTC sync would jump between about 80Mbps and 70Mbps depending on whether my neighbour was connected or not. It was also very noticeable during a power cut where the cabinet and my equipment on a UPS would stay up, the max attainable rate could jump quite a lot until everybody else came back on.