Day 92

A prophecy:
In the future, much farther away then next week or even next year, our people develop a technorganic plantlife that will come to be known as parrot moss.
When originally designed and implemented, this will not be its name initially; rather it will be assigned a serialized mashup of numbers and letters that are both boring and forgettable. This bio engineered flora will be cooked up by an intelligence gathering agency, in attempts to grow unassuming recording devices in public spaces. Not necessarily for use in espionage or political gain; in all likelihood it will be all part of a marketing campaign.
Regardless, the devices will start to malfunction.
They will do as they will be meant to do, which is to record the conversations of the unsuspecting, but they will also do what they should not: broadcast what they have record.
Hence the name parrot moss.
Upon discovering the flaw, the greenery will be removed and destroyed from public spaces, save for in one location: an indiscreet patch growing in a particularly charming public park.
This patch of parrot moss will remain in the park until humanity lives past its need for parks.
It will record snippets of walking dates, parents running their children to the playground, concerts at twilight, outdoor plays at dusk, bird songs at the dawn. An audio record will exist of all the sounds of life that have gone on around a patch of unassuming grass.
It will malfunction on occasion and begin to echo back all the samples stockpiled over the decades and the once charming park will be labeled as haunted.
A field of ghosts. That really is all ghosts are, echoes of another day.
But these firings of sound will be completely random, and those brave few who walk the abandoned park's paths will be treated to some singular auditory experiences. Half conversations being answered by long lost symphonies while dogs bark at a poor soul trying to recite Hamlet. No two encounters will be the same.
Finally, on doomsday, the last earthling will come to this remnant of a long lost society and rest their weary head upon the ancient moss.
And at that moment, the sounds and voices of civilization past, will all come together. And, despite being dead, their voices will rise and the song of silent ends will begin. A composition that only plays when a world ends.
And this will guide the last earthling into a blissful extinction.