In any city, in any country, go to any mental institution or halfway house that will let you in without question. When you reach the front desk, say to the worker these exact words: "I would like to visit the Holder of Dissonance."
Should a troubled look cross the worker's face, calmly turn and leave the building, and do not return to it for at least two whole days, or your mind will be completely and utterly destroyed by the horrors waiting for your return. If the worker's face remains neutral, you will be led to an elevator, and taken to a floor lower than the confines of the building.
When the doors open again, you will be in a cavern which seems to have no boundaries, and the worker will have disappeared. Make no attempt to locate them, or you will wander this cavern for the rest of your days. There will be a repetitive drum beat echoing around the cavern, a simple rhythm of four. Focus on this drum beat, and find the source of it. If at any point the drum beat becomes an untimely cacophony, stop and cover your ears the best you can, and shout with all of your strength "This is not the correct decision! I wish to talk!"
If the drumming becomes a precise, four-beat rhythm again, you have reacted fast enough and have been heard. You are free to continue to trace the source. If the white noise persists, nothing can be done. Your mind will slowly begin to warp as the drums tear away your sanity.
When you reach the area where the drums seem to be resonating from, state, calmly, that you wish to talk. If you have convinced the Holder, a large drum constructed of bone and flesh will appear from seemingly nowhere. Along with the drum, two twisted entities will also appear; flayed beings with tattered skin and distorted faces beating the drum with the bodies of loved ones. Show no reaction to this sight, do not scream or weep with fear, as it is an illusion. React, however, and you will be put to this fate, constantly being beaten against this drum, conscious the whole time, doomed to an existence of nightmares and insanity.
Approach the drum without hesitation, and firmly knock on it four times, in time with the flayed ones. Repeat this until the flayed ones stop, and the drum will open up. When this happens, ask "What happens if they are unheard?"
A boy of about fourteen, wearing bloodied flesh, should emerge from the drum. The flesh is the remains of past seekers who have failed to pass through. He will then go into detail of what would happen if everything was unexpected, from the clashes in the past to what would happen in the future. For the duration of his tale, look only at the boy. You will be tempted to look away, but do not give in to this temptation, or the flayed ones beside you will tear you apart, adding your remains to the boy's cloak of flesh.
Once the boy finishes his tale, the drum will shrink in size, until it is no bigger than a tennis ball. He will offer the drum to you. Take it without hesitation, and close your eyes. When you open them, you will be outside the building you started in.
This drum is Object 642 of 2538. When the time comes, everyone must know.
Credited to Ad man99