Virtually every public and corporate space I visit — lift, office lobby, grocery store, doctor’s office or petrol station, every space — has overhead speakers and a piped-in sound system, which has no reason to exist but seems to grow louder each year. Most places play the same twelve songs over and over, but the choice of music is not the main issue. The problem is that most people I know have ceased to notice this background and talk over it — again, more loudly each year.
No other society has ever performed this kind of giant experiment on themselves over generations, so no one has ever measured the long-term effects. I do know, though, that between the earphones, the MP3 player and the earplugs, a normal life is getting expensive.