The volume tab shows the current volume levels and vibration settings, which can also be adjusted from this tab. Changes are applied immediately.
It is also possible to lock the current states of volume on this tab using the Volume lock feature. If you activate this feature then you can adjust the volume only on the SVC Volume tab or through the SVC widgets.
Lock affects all other applications and hardware volume buttons. By default, it doesn't change the volume when switching profiles within the SVC, but this behavior can be changed in the application settings. You can also use the widget to turn this feature on/off. Keep in mind that it only affects volumes that are locked on the volume tab.
The feature can be useful in situations in which you do not want to change the volume, such as a phone in your pocket in combination with the accidental pressing of hardware buttons, listening to music or gaming.