New customer - poor speed

[#1]

I have switched from Sky Fibre to Plusnet Unlimited Fibre and speeds have been poor every day except in the first half an hour post activation.
My phone service switched to Plusnet on Thursday 3rd around 1pm, the broadband service didnt activate until 5am on Friday 4th. At 5.26am I did a speedtest on my mobile and got a download speed of 40.51Mbps, upload of 11.90Mbps and a ping if 19ms. A minute later I tested again as for some reason the speedtest used a server in London despite me being in Derby so I manually changed to a Nottingham server and got 51.73Mbps down, 17.62Mbps up and a ping of 30. Since then I have had a high of only 20Mbps and am currently getting 8.72Mbps down according to BT Wholesale. I have looked at the router stats and they state "Downstream: 64.88 Mbps  Upstream: 19.53 Mbps" so why is there such a difference between what the router is saying and what I am actually receiving. As it stands I am getting half the speed I was getting on Sky and less than a third of what I was estimated to get by Plusnet. I know I am still within the mystical first 10 days but I have never had an issue like this before.

[#2]

What does the Plusnet Line Speed show at https://portal.plus.net/my.html?action=data_transfer_speed ?
If not correct, phone/chat with Plusnet and get them to increase it.
Once correct (or if correct now), log onto the router, click "disconnect", wait a minute and then click "connect"
Try speed tests again, preferably using wired connection to the router.

[#3]

Quote

Estimated line speed: 78Mb (This may vary between 59.5Mb and 78.1Mb) - Checked on 2016-02-17 13:43:09 Current line speed: 21 Mb

I have tried speedtests after a restart (electricity went so thought why not test now) via my pc which is wired and no difference

[#4]

Sorry about this, can you try a single disconnect/reconnect and the speeds should be fixed.

[#5]

Getting 34Mbps now, still less than I had with Sky and less than estimated

[#6]

[#7]

[#8]

Are they still over a wired connection? Have you stopped any other usage as from those stats you've used nearly 60GB (which is easily achievable) in 15 hours.

[#9]

I have BT Homeplugs which I have found are throttling the connection to my PC. I get 30Mbps with the Homeplugs. I have just dug out an old laptop and it gets 63Mbps via ethernet so seems things arent too bad. Looks like Im going to wire the house properly.

[#10]

Good find, I'm lucky(?) in that my homeplugs don't slow down my 8Mbs connection.

[#11]

Quote from: Chris

my homeplugs don't slow down my 8Mbs connection.

At that speed how would you tell