Line speed dropped dramatically today

[#1]

From running at around 4500kbps download (router reporting 5248kbps) yesterday to 800kbps download today (router still reporting 5248 kbpsdata rate).
According to the last response you gave on my ticket #73971716, you said:
"Having checked I can see the connection has been up for the past 3 days at a profile of 1250kbps, our profile didn't appear to have updates so I've just done that now to bring that in line for you."
I immediately responded to this pointing out :
" I presume 1250kbps is a typo on your part, since the router is reporting 5250kbps at the moment."
The awful download speed we are getting now is in line with a 1250kbps profile......  If you have done this, can you please reset it to something sensible with the utmost urgency as these speeds are not "broadband".

[#2]

Still no better this morning.  No reply to the ticket I opened last night  (but at least it states that "Our tests have found a fault with your broadband service") or to this forum post.
Bumping this as the speeds are unacceptable.

[#3]

Monday Morning.. still no reply on the ticket and getting sick of seeing that grinning idiot and his fruit.
Speed still awful

[#4]

Hi, I've updated the profile to 4500kbps for you.

[#5]

Thank you.. that will do for a start.  Now all we need to do is to get the line speed I did have 15 months ago when all this started back.

[#6]

Have you tried a different microfilter yet ? Some of these seem to die gradually over time.
Also worth testing in the master test socket for a few days if you haven't already done so to see if that helps with the line speed.

[#7]

Thanks for the advice picbits, but I know the source of the drop in speed...
"Having checked I can see the connection has been up for the past 3 days at a profile of 1250kbps, our profile didn't appear to have updates so I've just done that now to bring that in line for you."