I'm not sure I get what your saying. Are you asserting that GP is confused about what they are hearing, or are you saying that the ultrasound is creating some

I'm not sure I get what your saying. Are you asserting that GP is confused about what they are hearing, or are you saying that the ultrasound is creating some kind of unpleasant interference that is being perceived instead? I've been able to hear in unusually high ranges my whole life into my mid-30s. Office, home, urban environments... distance measuring equipment, devices intended to repel birds and mosquitoes... things that are loud but "too high to hear" that wind up for me being "yes, that is indeed very loud and very high".