The way volume controls work in Windows Phone haven't changed much since the platform's debut. Basically, there's a single volume setting that applies throughout the entire system and to all installed apps – an inconvenient solution, as many WP users would agree. But according to rumors, Microsoft may change things a bit with the launch of the GDR3 update. Once the new software is out, Windows Phone 8 may finally get separate volume controls for the ringer and other media playing in any app...Source: http://www.phonearena.com/news/Separate-volume-controls-quick-settings-menu-coming-to-Windows-Phone-8_id46805
