I CANT FIGURE OUT HOW TO CHANGE THE GODDAM SYSTEM VOLUME.

tried with built-in clis:
pulseaudio-utils, alsamixer, amixer

tried with c libraries and all audio APIs i found in the developer api:
qmediaplayer, phonon.audiooutput.

this should SO not be difficult. anybody know how to do this? {programmatically adjust the system volume, such that the slider in the status bar also moves with it}