Why does my client [name withheld] have a high-pitched ringing in his ears? He was wondering is this the positive realm trying to signal me, or something not so positive such as EMF or WiFi sensitivity?

This, in fact, is due to spirit meddler interference with the cellular signaling and is a change in his nervous system perception they attempt to instill in many of their victims. Whether they are successful depends on individual sensitivity and susceptibility. Once instilled, it is hard to heal quickly because the changes are a consequence of a karmic event, and as such, are now under command of the body itself. This is something that can resolve over time but may not as well.