change detail in game an the sound?

I have 2 questions

1) I want the volume level of an audio source changed more with a var in javascript and how is that possible?

2) how can I change the detail in the game itself? as at startup

plese help :(

by detail you prolly mean quality. start here

The audio source you use has a variable called volume which you can alter directly.

If the sound is mono and is a 3D sound it'll get quieter the further away it is from the camera (and its audio listener). You can also edit this effect with the rolloffFactor variable.

http://unity3d.com/support/documentation/ScriptReference/AudioSource.html

e.g.

audio.volume = 0.2;

AudioSource has a property called volume. if you have many audio clips you can play them with audio.PlayOneShot with different volumes.