bt have told me there is a problem with my broadband and have said I would receive a refund for the 2 years of fault once fixed. I have spent hours on the phone to somebody I can barely understand on several occasions with no refund and problem still not fixed. They haven't even sent an engineer out.
and use this speed tester then carry out the further diagnostics and post back a screen shot of all the results including your IP profile for up and down. This test must be done with a wired connection.