My MTB is afflicted with clicking. BB has been stripped and serviced, new rear wheel, pedals tightened, seat and post checked, bouncy forks serviced... and... click clickety click.
Then my right hand crank sheared off one morning just before parliament square. (It was an interesting sensation still being clipped in and trying to shake the pedal and crank off my foot whilst not falling into the traffic behind me).
I think it still clicks, even now.
Sorry, I know this isn't helpful but helps me to talk about it.