Hi I own a Sony STR DA50 ES Home Cinema receiver. When using the EQ or bass boost modes there is a definite "hiss" added to the sound. Even with these modes defeated, when in the Sound field mode (especially Dolby/DTS 5.1) the dreaded hiss noise returns. Any other members have this amp and this problem? Its really annoying and i wanted to know if it was a "characteristic" of the amp or a genuine fault. Thanks Mark