[elfchief]

Pretty much this. I have a pair of studio monitors set up for music and tuned for music. Game audio and random youtube videos don't sound so great with that setup, so I don't want it to be my default.

Sure, I could change the default every time I fire up Spotify, but that's annoying and I really shouldn't have to do it -- this kind of setup is not that unusual for music lovers, and it's not a difficult feature to add.

[true_religion]

Have you heard of this http://www.chevolume.com/

It lets you set an app to use a default audio device, which may solve your issue with spotify. Some apps just ignore it, and only play through the system default though.

[FatalBaboon]

Or use pulseaudio under Linux and enjoy any setup you like of inputs and outputs!