I installed PCLinuxOS 2010 the new release
But my friend, there are a few different releases of PCLinuxOS 2010
KDE and KDE Minime / Gnome & Gnome Zenmini / LXDE & LXDE mini / E17 / Phoenix
So it's always best to supply as much info as possible relating to the problem AND the OS version and hardware specs, as that way forum members are far more likely to offer an accurate answer.
KMixer has an icon in the right hand side of the taskbar/panel which allows you to modify volume and different sound settings