This post started out as me just posting a joke, but then I thought too hard about it.
Passenger: Why was the flight delayed?
CSA: The pilot didn't like the sound of the engine.
Passenger: Did they get another engine?
Old Ending: No, they got another pilot.
New Ending: No, they downloaded new sounds.
They're talking about putting artificial sounds on electric cars so that blind people can hear them. They already have artificial pre-stall warning symptoms (i.e. the stick shaker) on airliner flight decks, to mimic the feeling of the stall buffet in the airplanes most pilots learned to fly in. Perhaps someday there will be a reason to use artificial engine sounds to mimic the sounds pilots are accustomed to in monitoring our engines. Detonation, backfiring, missed cylinders, loose flyweights, or "scary banging sounds."
Usually gauges provide the information we need, but there have certainly been many times when an engine sound has made me look at the gauges. Gauge irregularities make us listen to the engines (make us look at them too, that's actually part of the procedure, to make sure they aren't on fire).
There's an unexpected aviation connection to breaking news. Prince William, who is second in line to the throne and will probably become the King of Canada someday, has just announced his engagement to a woman who is the progeny of a flight attendant and a flight dispatcher. Long live the Queen!