Upload speed collapse

[Forumcloud]

Here in Stamford, Lincs, my download speed (measured at the hub) has for years been, and remains, around 49 mbps. Upload speed has always been about 14mbps until today when it dropped to just over 2 mbps. Download speed remains as always. Odd that just the upload has dropped.

[JohnC2]

Hi @Forumcloud, sorry that your upload speed has dropped significantly.

If your still experiencing slow upload try a factory reset of your BT Hub.

Cheers

John

[Forumcloud]

Update - a day on my downstream speed is still normal at 49 Mbps but the upstream is still at under a tenth of the steady-state value. It is now at 1.14 Mbps. I have restarted the hub about 4 times; no difference. I have not done a factory reset but see below.

I have spoken with a very helpful person in the BT Faults dept and he was unable to explain my problem. As a starting point he will send me a Smart Hub 2 (I am present, on Smart Hub) and that has been dispatched. I rather doubt that it will make any difference but it is good to have the latest Hub. He will call me next week to see if there has been any improvement.

According to BT’s online checker there are no faults in my area.

So thus far I am pleased with the support I have received from BT.

[imjolly]

As you have a new SH2 on its way you could try a factory reset by holding recessed button on back for 20/30 secs until lights flash

[Keith_Beddoe]

A loss of upstream connection speed can be caused by a deterioration in the high frequency response of the cable pair which would not be detected by the normal BT line test.

Its also possible that a faulty port in the cabinet could be causing this. This could be proven by Openreach checking the performance at the cabinet, with the local pair disconnected.

The picture below shows the frequency distribution of the broadband carriers, and you will see that a large proportion of the upload bandwidth is at the top end of the spectrum. (Look at the VDSL section)  Unfortunately that is the area that is affected most by any deterioration in the line quality. This can be cause by moisture ingress.

Assuming you have not made any changes to your internal wiring that may affect the frequency response, then you are possibly looking at a line or equipment fault. 

[Forumcloud]

Many thanks, Keith and imjolly - extremely informative. If a router rebuild / new router doesn’t solve my upload position I will be able to explain all this to the Faults man next week when he calls. He can then get someone to look in the cabinet …. (which is 600m away - not ideal).

[Forumcloud]

UPDATE: in the event BT sent me another SmartHub1. I assumed that the SH1 had been completely replaced by the SH2 so was disappointed to receive the SH1 but as it was FOC I can't complain too much.

I set up the new SH1 and the issue was partly solved. The speeds at the hub were 49up/11down, which is a lot better than the 49up/0.8 or so down that I've had over the last few days. 

I say that the problem was partly solved because for many, many months I've had more like 13 or 14 down. When I spoke to BT Faults they concurred with that; 'We can see that you've had rock solid 49/14 for many months' they observed.

So when they call me next week I will report that the immediate issue has been solved but there has still been sudden drop in upload speed, perhaps for the reason that has been mentioned in this thread.

Also following on from advice from responders, I factory reset the original SH1 today then tried that. As might have been predicted both the download and upload speeds were identical to those shown by the brand new SH1.

Things learned: (1) sudden drop in upload speed - rebuild your SH1. Doesn't take long. (2) Upload speed can drop independently of download speed and there are technical reasons for why this might be. (3) BT Faults, once you get through, are helpful.

I will update further if BT are able to get my upload speed back to where it has been for many months.

[Forumcloud · Accepted solution]

Well after a period of stability it collapsed again, though to 5mbps which is better than below 1 mbps before. I called BT again and they sent an engineer the next day. He came to our house and confirmed that all was well with our wiring and the wiring from outside to the master socket. He concluded that there must be a problem in the cabinet. He went to the cabinet and shortly after called me to check my speed. 

Before: 49 up, 14 down (but sometimes 5, and not stable).

After: 63 down, 19 up. Seems stable so far.

Not bad FTTC speeds at 617 metres (according to BT) from the cabinet.

Excellent service from OR Engineer Steven.