I have had it since I was kid. I used to buy into the idea that I was hearing the hum of electricity or electronic devices. It wasn't until I could still hear it in the middle of nowhere during camping trips that I knew that it wasn't but didn't know what it was. I just had to get used to it and let other sounds distract me from it. I went to an audiologist to get my hearing tested last year, and she said that I was probably part of the small percentage of people have have it for no obviously apparent reason. (i.e. I don't suffer from hearing loss or apparent damage that causes it). Since I was more concerned with hearing loss at the time, I didn't really think to inquire into ways of dealing with it. It came back to the forefront of my mind because I will be trying a float tank today, and I forgot to submit music before the weekend for them to try to upload to their system for me to listen to while I am in the tank. I am hoping they have something there that I will like enough to use, otherwise, it'll not only be a first float experience but a first experiment in meditating in a totally silent environment to deal with the high pitched tone . . .