Worth noting on the BT wires that some (I don't know from when) are aluminium and can be more problematic than copper.
Discovered this when we had a phone fault some years ago when the BT engineer explained what had gone wrong. (one of the pair "broke" when disturbed during work on an adjacent pair)
Aluminium also suffers from surface oxidation which leads to bad connections
Another good speed test site
Speedtest.net - The Global Broadband Speed Test
