Disable headphone play/pause button?

Whenever headphones are plugged in my MacBook Air frequently falsely registers the headphones' play/pause button as being pressed, so it will either open iTunes or stop/start a song on iTunes.

When I'm using another application the simple solution is to open QuickTime Player, that overrides iTunes. Great.

However, when I'm wanting to listen to iTunes itself the music keeps stopping and starting. Not great.

How can I disable the headphones' play/pause button for iTunes or in OSX in general?

Originally posted by @barrybarrybaz