Logitech Z560s...hiss at high volumes

[dmw16]

I just got a pair of logitech Z560s and I love them, but I just had one question. Should I hear a hiss/white noise type of sound at very high volumes? The only time I really hear it is when I crank them up but no sound is coming from the PC or when listening to classical music. Is this just something that speakers do when you crank them?
thanks,
-doug

 

[dmw16]

bump

 

[Earwax]

I got a pair of Z-560s. They will hiss if I adjust the manual volume control past about 3/4 of the way. You shouldn't need to turn it up that high if you adjust your system volume though. And it shouldn't be hissing if it's less than 3/4 of the way up.