Hello guys

Recently i installed Simon the Sorcerer on my 486 DX4 120Mhz and can't hear the voices.
When i installed it i tested the sound with the setup utility of the game, i hear the voices and music clearly.
Here's my setup:
486DX4 120Mhz with 64 mb RAM
Sound: Creative Soundblaster AWE64 and Roland MT-32
Graphics: Matrox Mistique 4Mb

You can see in this video on youtube the voices playing clearly, in my case i just get the music and the subtitles.
What am i doing wrong ?

https://www.youtube.com/watch?v=_3PQnmcD_G8