Downloads speeds much lower than previously, any reason why?

[#1]

HI
Since I got fibre just over 2 years ago, my download speed has always hovered around the 7MB/s area but the last week or so I've noticed that it seems to have dropped down to about 5MB/s.
I looked on the BT speedtester site and it reported my sync as 46.97 Mbps or a max achievable speed of 49.99Mbps, this puzzles me as my connection has previously always been around 65Mbps or there abouts.
Any thoughts on why this has happenened?

[#2]

Have you tried power-cycling the Openreach modem?

[#3]

I use to have 65MB myself so i know it sucks when you loose a chunk of it,  sadly you have to be below your estimated range before Plusnet / BTW deem your loss worthy of investigation, I have a feeling they will say your still within that range if it's anything close to what mine is.
you could try a Modem reboot but only do it once, but even then I very much doubt it will help.

[#4]

Hi @valve90210
Diagnostics aren't showing me any obvious problems.
Were you connected over ethernet or WiFi when you did that test?