I have been experiencing an unstable internet connection over the past 12 hours, I wouldn't be too bothered but I had the exact same problem for 4 days starting the Friday before last. My connection is approx 5 - 6 mb but during a speedtest atleast twice the connection will drop to either dialup speed or nothing (for a split secound) then go back up to normal speed.
This repeats constantly, its especially noticeable playing online games (xbox etc) as causes constant disconnects. My location is Herefordshire if there are any current issue's here, however Status page does not mention any.
But interestingly previously the issue resolved itself after several days. I am using a BT Homehub 2 on the main socket.
do you have an NTE5 master where you can remove the bottom half and connect to the test socket behind?
It is a know problem with the HH2 that sometimes when accessing the adsl stats in hub manager the hub resets the connection. this has been a problem for 1yr+ but the introduction of the HH3 has resulted in no further progress with a fix