Honda clicking noise when breaks applied

I have a 2002 4 dr 4 cylinder Honda Accord. The front breaks are 8 months old & all mounting bolts are tight. When he breaks are applied, there is a high speed clicking noise coming from the front of the car, which slows down as the car slows & stops before the car stops. The clicking comes & goes from one day to the next. What could be causing this noise as the breaks are applied?