Problem with Theta Miles


Hello, new user from Norway!
I've got a Theta Miles with a problem, it's very noisy! It's like standing in the shower, a remarkable hiss from the speakers, playing cd or not, it appears the moment I switch to the input it uses. Tried XLR or RCA, same problem. The problem follows the signal strength, it's worse when the output it set to maximum. (I use a integrated amp, and I've tried other amps, same problem) I use a rather sensitive pair of speakers (100db sens) but it's a problem on other speakers too, the former owner never had the poblem because it was connected to a poweramp directly and driving very low sens speakers (81db). The problem occurs in both speakers.

Any suggestions?

(Pardon my clumsy English, I'm out of practice)
hifiguru1969