Have you heard of this http://www.chevolume.com/ http://www.chevolume.com/ It lets you set an app to use a default audio device, which may solve your issue wit

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