Gordon, that can get complicated with master licensing for original music. Then there's the mechanical fees. Check out the Harry Fox Agency for more information. Also, if you are using someone elses music, you'll have to make sure that the publisher and the composer agrees to what your project is. We learned that the hard way with mixing orgasms to music and we LOST a LOT of money due to licensing issues. Anyway, we found an artist that's willing for us to mix the orgasms www.tritriadproductions.com/prev....html to his music! Now we're mixing nature sounds to O's!

Good luck!