Tweek Volume of group of sounds

Unity
1

Hi this is my first post here, i would be gratefull if someone tell me how to change the volume of number of audios together or to mute some audios and increase or decrease the volumes of couple of audios together. . .i am using FMOD1.0.8

2

Please see this post http://www.fmod.org/questions/question/could-i-change-volumes-of-fmod-within-unity/