Apparently the original recording was “Laurel”. Then someone filtered it to remove some of the bass components. Based on our hearing sensitivity, some of us hear “Yanny”.
My wife hears “Laurel” and I hear “Yanny”.
There is an link on the New York Times site that has a slider that varies how much of the bass is removed:
https://www.nytimes.com/interactive/2018/05/16/upshot/audio-clip-yanny-laurel-debate.html
You can vary the filter so that everyone hears “Laurel” or everyone hears “Yanny”. You can even find a spot for most individuals where they hear a mix of the two words.
The speed-up or slow-down effect you describe is pretty much the same thing, since speeding up means shifting to higher frequencies.
So now there two things that the NYT is good for: real-time election night results, and disntinguishing Laurel vs. Yanny.
I might question the election results. After all they are a big time liberal rag that lies all the time.
rwood