USING THE HEADSET
Prior to actually using the headset you should head onto the official SteelSeries support page and download both the driver package and the firmware update tool.
The firmware update tool is not only for the Diablo III headset but for many other devices from SteelSeries. The firmware updates takes but a few seconds to finish after which you need to unplug the headset and then plug it back into the USB port.
As you can see the control panel is also designed after Diablo and gives you the basic functionality you'd expect from a high quality stereo headset. So you can configure the audio levels through a 4way equalizer, adjust the illumination density and pulsation, create profiles and link them to specific games.