As most people enjoy and rely on communication to effectively play the game, the in-game volume settings don't actually provide a decent modification for sound effects and VoIP.
I have a solution that doesn't require you to turn your master volume UP and go deaf trying to here your teammates over loud music, gunfire, and explosives.
Go into your sound mixer.
(For Windows XP users, try right clicking to open the mixer)
Then turn the APBprogram volume down (about 50%) and leave the VivoxVoiceService (VoIP) up.
Then just go into the game and manually adjust your Master Volume to the desired setting.
Hope I could help Enjoy!
Edited by Kimba, 03 October 2012 - 06:20 AM.