Assuming that you use Windows as it's a prety common OS.
Powered speakers? Also check that the power cord is plugged into the wall outlet or your power strip. Easy to forget...
Next to the clock on the tast bar, you should have an icon looking like a speaker.
Click it.
Is there a check in the Mute check box? Uncheck it if needed.
Where is the slider? Push it up if it's at the very bottom.
Double click that same icon. It brings up the Volume Controll dialog.
Uncheck any muted controll.
Adjust the sliders as needed. The main slider on the left and the "Wave sounds" should be set relatively high, usualy, over the 50% mark.
The Synth controll adjust the volume of midi files playback.
Possible cause:
When you adjust the sound level in some applications or games, it changes the global setting rather than adjust the sound level localy for that application/game. The programmer who use that method is often lazy and don't bother reseting the original volume on exit.
Electro
May 2011