Ahhhh our friends at BT....
I get exactly as you mention. If there is a storm in the area, I lose my connection every 4 minutes. You can set your watch by it. When I asked BT about it (which in itself once took 3hrs to get through), they said storms may have an effect on the line. When asked about why the phone still works. silence fell upon the call......
Different topic, although sticking with BT, my Outlook Express somehow lost it's logon details. I tried to get it working again and failed. I called BT for "email help". After spending 30 minutes on the phone to a woman in India, she told me "Sir, your settings have changed and you should go to PC World and get an engineer to back up your data and re-install Outlook Express. That will cure the problem. Are you happy with the service provided Sir"....
I replied "No, goodbye."
I then called BT back and spoke to another person, in India, and after about 30 minutes, he sorted the problem. McAfee had apparently duplicated a file within Outlook Express. He deleted it remotely, rebooted, and bingo......
So, the moral of the story is........just hope it doesn't rain and use webmail