In case you've noticed this (or maybe you haven't and are curious how it works):
When you upload a sound into Sansar, it's automatically normalized to a peak of -3 dB.
Basically, if you upload a noticeably quiet sound, its volume gets auto-adjusted to be louder, so that the loudest part of that sound reaches -3 dB.
This is useful if you don't want to fiddle around with a sound editor — you can always adjust the Loudness slider for an audio emitter to your liking. We think simply doing it this way makes things more convenient for audio newcomers.
More background: http://www.learndigitalaudio.com/normalize-audio
However, if you're experienced with audio, I know in some cases it may be undesirable to retain relative dynamics... like if you upload a really quiet room tone and place it in a scene, it'll be quite a lot louder by default. The upside is you can use Audio Preview to hear it right away, but it'll require post-adjustment.
We'll continue to improve the Sansar audio system to make it fast and fun for you. Just wanted to spread awareness of this (and I'm curious who else did notice?)... happy soundscaping! :)