Tweeter hiss?

Hi, I'm new to the world of hi-fi and audiogon and was hoping someone out there could help me.

When I have my amp turned on (an integrated) with the speakers connected, but not the CD player, I hear a hiss coming from the tweeters of both speakers. This is with the volume completely turned down. Is this normal? If I turn the volume up the noise increases. It's not very loud by any means - I need to be within a foot of the speaker to notice it. Is there something wrong with my amp or speakers? If music is playing then the hiss is covered by music. I am also unhappy with my systems general "brightness" and fatigue factor and I wonder if this is related to my hiss-tweeter problem.

Thanks in advance for any suggestions.
(Rotel integrated, B&W 601s3, audioquest cable)