I need to set the master speaker volume, or at least read the master speaker volume, just like when you click on the left or right arrow when you are in a cell phone call. Anyone can give me some hint on where should I look at?

I tried the CMdaAudioOutputStream.SetVolume(). It can change the volume in a very small range. And seems that it apply the change on top of the phone's master speaker volume setting. Such as, if the phone's master speaker volume is set to high, my volume is also high. Change the parameter of the SetVolume() will only give a small change on the high end.

With the build in Music Player, if you change the volume in the Music Player, it also apply to the master speaker volume. Anyone knows how to do this?

Thank you very much.