Audio problem.

[Febry Suhartono]

Hi,
I've been using OpenMeetings for the last 2 weeks and i'm doing a 5 persons 
conference room.I'm having an issue, the audio quality is not good enough, the 
volume of the users (except the moderator) is very low.Already adjust the 
volume control on each users but still the volume is very small.
What can i do to make it better?
Best Regards,Febry