Interesting link:

http://www.scientificamerican.com/blog/post.cfm?id=music-to-the-ringing-ears-new-thera-2009-12-28

A distressing condition. Beethoven suffered from it, reporting a rushing and roaring in his ears; Brent Michael Davids has composed a 'Tinnitus Quartet'; Smetana included the high-pitched 'E' he constantly heard in the final movement of his String Quartet in E minor.  It's at  3:46.