Yes, I know that this is a lame question, but I bought a Logitech iTouch KB with the volume controler on it. The problem is, that this knob controls the system volume, so I put my speakers volume on 50%, and I control the loudness by adjusting the system volume with the controller on my keyboard. It is ok, to contorl the overall sound this way, or I should use the normal sound controls on my speakers?

hm if the output volume of your soundcard if very quiet then you'll have to gain your amp a lot and this will bring noise to the whole thing. but if the output volume of the soundcard is too high everyting will clip. i think if you don't enable 100db by a software preamp a system volume of 100% should be no problem.

this also depends on the soundcard i guess. they have all a little preamp or output volumes. not that you could hear anything with that output volume but at least my standalone cdplayers have all different output volumes.