Occam's (and Halon's) razor says that volume is set to an arbitrary default ("loud " == "audible") and no one cares to change it. It boggles that any other opti

Occam's (and Halon's) razor says that volume is set to an arbitrary default ("loud " == "audible") and no one cares to change it. It boggles that any other option is in consideration. In airline has done actual measurements of attention vs volume.