Broadband unusable until after midnight

[#1]

The past week or so my line speed has been appalling & getting steadily worse
Never had the fastest speeds where i am given the remote location. However, after moving to plusnet i have been getting a constant 7meg speed. Which compared to the mega throttled supposedly 2 but actually 0.5 line from AOL has been a godsend.

However. Like the header says. The last week (apart from the hours between midnight and about 8AM. My broadband is unusable. I found myself waiting 5 minutes on a 3 second .gif to load yesterday like it was 1997 and Dial-Up all over again.
Speedtests are showing linespeed down from 7meg to 2meg. But in no way am i seeing 2 meg speeds. Its more like 56k. I can hardly watch a gif never mind a crappy quality youtube vid
I havent even used a third of my 60GB limit this month so its not like i have been hammering the line

Please sort this out.Its actually faster for me to use my Mobiles broadband and im in an area that doesnt even get 3G

[#2]

Happy to look into it for you, I've checked over your account and there's no issues with the profile I can see. Likewise it's showing as 7150 on BTs side, so it doesn't look like exchange profile is slowing things down either.
I suspect therefore it must be a fault somewhere... have you run a BT speed test (http://www.speedtester.bt.com) and if so what does that show both for throughput and the profile on BTs side?