WEBF
Now your phone line has been replaced and therefore your connection problems sorted, you might want to think about phoning your local telephone exchange and asking them to turn OFF the (I think it is called) automatic levelling control. This feature basically ensures that the volume of anyone calling you (in your phone speaker) is kept constant even though as we know different people speak at different volumes. Ever noticed this on a phone, how the voice volume remains the same even with different people?
Anyway by getting this feature turned off, you can increase your data-rate. The downside is that it wont now be regulating the volume of your voice comms, however a small price to pay (just turn down the volume on the handset if able).
Now I know where you live, it is quite close to where I used to live and I got this thing turned off and as a result my data-rate went up 20%. You have to phone your local exchange and talk to an engineer, not BT residential services (as they wont understand what you are going on about). Just a thought.
Oggin