Large reduction in broadband speed and Fibre 2 option no longer available.

[Matt342589]

I have lived in the same property for almost four years. The property is in a rural location and I am less than 300 metres from the cabinet. For over four years I have been on a Fibre 1 package which was upgraded to Fibre 2 speeds. My download speeds were consistently around 75 Mbit/s for all of this time.

At the end of last year this changed and my download speeds dropped to around 65 Mbit/s. At the start of this year the speeds dropped again to a fairly consistent 55 Mbit/s. I assumed the Fibre 2 speeds had been removed from my Fibre 1 package. However, when I login in to BT to upgrade my package the only options available are packages with a maximum download speed of 55 Mbit/s.

The output from the Broadband availability checker appears to show my maximum observed downstream at the end of last year was 60 Mbit/s.  The downstream handback threshold is higher than this, as is the line rate.

The maximum observed downstream value in November last year was around 75 MBit/s. My observed downstream rates are now 55 Mbit/s in January. 

I have spoken to two capable BT engineers, but as of yet nobody has been able to conclusively state why would happen. Can anyone explain why this would happen or has anyone experienced anything similar with BT?

[imjolly]

welcome to the BT community forum where customers help customers and only BT employees are the forum mods

in order for the forum members to help please can you post the stats from your router (if hub enter 192.168.1.254 in your browser) and if  HH5 then go to troubleshooting then helpdesk and if HH6/SH2 then advanced settings then technical log information . 

Have you tried the quiet line test? - dial 17070 option 2 - should hear nothing - best done with a corded phone. if cordless phone you may hear a 'dull hum' which is normal

Someone may then be able to offer help/assistance/suggestions to your problem

[Matt342589]

Thanks for the quick response!

My modem is an HG612. If I run the linestats command I receive this in response:

xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 25777 Kbps, Downstream rate = 77876 Kbps
Bearer: 0, Upstream rate = 20000 Kbps, Downstream rate = 60000 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Discovery Phase (Initial) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2800,3967)
Medley Phase (Final) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2800,3967)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 25777 kbps 77876 kbps
Actual Aggregate Tx Power: - 0.5 dBm 13.1 dBm
====================================================================================
VDSL Band Status U0 U1 U2 U3 U4 D1 D2 D3
Line Attenuation(dB): 2.5 18.3 21.1 N/A N/A 10.1 27.4 29.5
Signal Attenuation(dB): 2.5 17.3 20.4 N/A N/A 10.6 27.6 29.5
SNR Margin(dB): 9.6 9.5 9.5 N/A N/A 11.6 11.6 11.6
TX Power(dBm): -15.0 -26.2 -0.7 N/A N/A 9.8 7.9 6.9

I have tried the quiet line test and couldn't hear anything. However, I don't have a corded phone.

[imjolly]

If there is no noise using cordless then that is good

there is nothing in stats that shows internet connection time not system uptime but your noise margin is high as normal is about 6db suggesting your connection has been  dropping or  you have been resetting trying to improve speed or maybe combination of both.  This has resulted in a reduction of speed as your attainable is 77mb so should be able to get nearer that about 75mb

[Matt342589]

I haven't noticed any line drops. I powered down the modem and reset it once on the same day around 6/7 weeks ago when I first observed the problem.

Both the modem and my router report a WAN uptime of 5 days 22 hours. It is quite possible that the drop out around 6 days ago was an electricity cut. Those kind of cuts don't seem to have been an issue in the past though. I am sure of this because we had fairly regular cuts in electricity during upgrades to infrastructure a few of years ago.

Edit: Thanks for your help with this. Can I ask what length of time would be considered a stable connection for a modem?

[imjolly]

a good stable connection could be months.  My own SH2 stays connected and is only reset manually if I need to make some changes or with a firmware update so is normally months

with your high noise margin that certainly suggests there has been line problems causing drops in connection. Power cuts would be treated as drops in connection and if there was a few in short time scale you would get a rise in noise margin and a drop in conenction speed as DLM made adjustments to try and stabilise your line

is there nothing in modem stats that shows dsl uptime?  Maybe logs where you could trace drops in internet connection.  System uptime just tells you how long since last power down but not internet connection time

[Matt342589]

I can see how the noise margin would suggest line problems and drops in connection. However, we have been remote working everyday since march last year from 9am until 5pm. Nobody using the connection has noticed any drops at all. We have been using remote desktop, streaming radio and tv, zoom etc, and gaming daily without any issues at all.

The only difference I have observed is a gradual reduction in my maximum download speeds.

Am I correct in thinking a drop in connection would be a noticable event?

I will have a look for logs indicating drops in connection. However, as I have been using connection every day during this time I am not sure I am likely to find any.

[Matt342589]

I checked for logs indicating a disconnection there were none. I have confirmed this with BT technical, they have confirmed that the line is stable and they do not see disconnects at their end.

I have been provided a few possible reasons for why this might have happened:

The cabinet in my area is now overloaded and Fibre 2 speeds are no longer available to me. Given how close I am to the cabinet this would indicate that nobody in the area can sync at high speed anymore.

An upgrade BT provided my package has been silently rescinded. This could be true but it doesn't explain why I can no longer purchase a package at the speeds I have been using for the past four years.

Could anyone comment on the likelihood of either of these reasons for being rebanded to a different speed?