I have a suggestion for a masked sound that perhaps will help people with tinnitus like @Azriel.
There are some audios in youtube that are supposed to help people with tinnitus by playing sounds of a certain pitch for an hour or so such that when people stop listening to the sound, their tinnitus goes away as throughout the one-hour audio, they were matching the tinnitus noise in their heads with the noise produced by the audio.
Not sure if it will work but just an idea.