Hi I've just bought some bluetooth headphones to replace my ageing wired set. Unfortunately, they require a preset in iTunes to make them sound good. However. When I switch back to my external USB speakers, that preset sounds crap. I believe I can assign a set equalizer preset based on the song playing, which is not exactly what I want. Is it possible to have iTunes change the preset based on the current output device on OSX? Save me having to switch it each time myself.