like ioneabee, I have got infinity installed to my home. However recently I have noticed that at certain times I get 2.9 MB, consistently at certain points throughout the day then at others it goes straight up to the normal speed of 38MB. It's not due to excess demand on the exchange and a fight for bandwidth as the speed is extremely accurate, day in day out like clock work.
So, I made the mistake of thinking I could get someone in a BT call centre to fix my problem. After 30 minutes on the phone to Chennai I got nowhere, they insisted that it was a known fault on the line and it will be fixed on Thursday, this was last Thursday and the problem still persists.
I despise BT with a passion. RANT OVER