Freddie

Can anyone tell me how to choose your setting for speed compensated volume? My 2011 edge has values from 1 to 7 or off. I know what off is for but what's the difference between 1 and 7. Does 1 mean it will increase with speed at a small amount so that as noise in the cabin increases the sound system will not stand out as much and 7 mean that it holds it's net volume (total volume - cabin noise) better? thanks, Freddie