Aren’t the complaints driven by ulterior motives like trying to shut down local industry?
In many cases the sufferer has no idea where the sound comes from. This being the case it is unlikely that the complaint is motivated by ill feeling because there is no perceived ‘culprit’ to direct the feelings against. Cases where the source of the perceived sound is not known are generally consistent with other cases, so ulterior motives do not explain the phenomena that are observed.
