I'm writing a sound manager to support wavs, and ogg vorbis files, and everything seems to work except for when i try to set the volume for the ogg files. Can anyone help me on what the proper function or way to set the volume is in c++. Thanks.

First question is - what API are you using to play the files? C++ itself has no way of playing back music files, let alone setting their volume.

direct sound

I solved it, the problem was that i was not setting the dwflags values for the DSBUFFERDESC struct.