anotherUltra-slowFTTC download speed

[#1]

Been happy with my speed up to now been getting a rock solid 73Mbits well over a year, wake up this morning and was getting around 8.63mbps down 8mbps up,
so this is my usual speed
Estimated line speed:
    There's no speed estimate currently held on your account.
Current line speed:
    77.4 Mb
did  a speed test on BT speedtest here is the Result of a BT speedtest
Results Image not loaded

1. Best Effort Test:
Download Speed : 9.14 Mbps
2. Upstream Test:
Upload Speed : 7.3 Mbps
this is the speed i get on speedtest.net

So something as killed my speed 

[#2]

Ok just powered down bt modem and router, left them switched off for 5mins, ran speedtest.net and got the same results 
Looks like i need some help now.
Any plusnet staff can help plzz.

[#3]

Morning darklight,
Sorry to hear you're having issues with the speed of the service, I've just taken a quick look over it for you and everything seems to be showing as correct with regards to the speed profiles. Are you able to perform another BT speed tests to see if we can glean the additional details for our checks?
I understand that this failed for you the first time round however this could now have changed, if you're able to get this to run would you also click on the  'Further Diagnostics' button so we can grab the full suite of results.

[#4]

Here is another  BT speed test
Results Image not loaded

1. Best Effort Test:
Download Speed : 8.33 Mbps
2. Upstream Test:
Upload Speed : 7.43 Mbps

Still looking bad, i've also this morning well just called your support to log this proplem.
anything else i can do to fix this problem?
The support said to power down my modem and router for 1 hour see if that would reset it, i'll try that now

[#5]

ok reseting the modem and  router did not work powering it down for 1 hour did not work.  
Just wondering as DLM kicked in on my line, or banded?

[#6]

@Adam C
I've run the speed test with the  'Further Diagnostics' button through out the day yesterday, again this morning, still no change 

[#7]

Hi darklight,
Sorry to see this is still an issue.
I can see you've raised a fault which is exactly what we'd advise next.
Bear with us and a member of our faults team will be responding to ticket  89931588 soon.

[#8]

@_Adam_Walker_
I'll be waiting doing the  BT speed tests throughout the day, just wanna know if DLM is on my line, must have been a massive catastrophic load of errors to make it drop from 73 to 8.