Attach Sound Problem

I’ve attached more that 10 files from the library to movie. All the sound objects are loaded in different levels targetting on different movieclips. Everything is working fine but the sound volume is low. The setVolume () method i’ve given for a testing but while playing we feel the sound volume very low. Direct play button in the library the sounds play very clearly without any distortion. I wonder what is going behind the scene. Any idea :puzzle: