It would be helpful to have a full listing of music venues phone numbers, specifically their box office numbers.
However, the one i am trying to find right now is The Borderline. Orange Yard, off Manette Street, London W1D 4JB

Box office numbers for venues aren't necessarily to the box office at the venues themselves. Quite often they are provided by outsourced providers such as TicketMaster.

Is the box office for this venue at the venue or a call centre elsewhere? A link to the venue's website might help.