Clutch has started to make a clicking sound when I depress it?

I have a Mitsubishi Lancer 2004 1.6. The clutch has started to make a clicking sound when I depress it. The sound does not come from the pedel, but from what looks like some kind of cylinder under the hood. Attached to the cylinder is a lever that moves out when the clutch is used and it is there that the sound is coming from. It always makes three clicks. What is causing this and how can I fix it? Thanks