I have a Krell Showcase using Balanced cables running to an Outlaw 7500 5 channel amp. When I select the DVD digital inputs from optical cables or the 7.1 analog inputs, the speakers are dead quiet (no music going through at the time). However, if I select one of the analog inputs when there is no music going through them, I hear a very slight, high pitch tone through the speakers. You have to place your ear next to the speaker to hear it clearly and it is barely audible from the listening position on the couch. You would only know it was there if it's late at night, the kids are asleep, and the house is totally quiet. If I go to the straight pre-amp setting on that input, the noise goes away. According to a Krell guy, he thinks the noise may be inherant to the Krell processor due to the DAC, which is out of the loop in pre-amp mode. Has anyone else experienced something similar?