Remove the Bell Wire from your BT master socket? Might not give you a huge boost, but what have you got to loose?
Im 333m straight line distance from the exchange, when I provisioned my LLU connection I was getting 14.5mb down and 1.3up, removing the bell wire bumped me up to 19mb down/1.4mb up.
Im 333m straight line distance from the exchange, when I provisioned my LLU connection I was getting 14.5mb down and 1.3up, removing the bell wire bumped me up to 19mb down/1.4mb up.

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