many devices emit various high frequency tones that might be revving you up. In fact, when I played my T tone to a friend, he said "that's exactly like the noise my laptop makes, so I hear that a good 8-10 hours a day".
It's odd because I did not hear the high frequency tone until after I had my dental implants, and now it's almost persistently there unless I sleep for a solid 8-10 hours. It's hard for me to determine whether it was the drilling that caused the initial damage, or the implants are somehow amplifying/picking up the sound like an antenna. If I put enough distance between myself and the laptop, about a meter, I can hear the humming of the fan and it almost nullifies the high-pitched tone. 1/2 a meter away and it's almost intolerable. If my ear canal has sustained structural damage, I don't think my tinnitus will ever go away.