Very annoying hiss - can't ignore it!

I had a set of Harmon Kardon Sound Sticks for many years and they served well. Passed these on and bought this Bose Companion 3 as a replacement. The constant hiss from the two small speakers is very, very annoying. It is very evident when music is playing at low volume, and impossible to ignore when no music is playing. I really wanted to like this set-up but can't as it stands. I went back to the shop and the shop demo model has the same hiss - tho maybe not as much. I now have to wait a couple of weeks for "testing" and think I will have to look for an alternative. Very sad, disappointing and annoying.