My Reduction is causing a hiss. Sounds like a steady ocean noise. For the most part it has been playing perfectly for over a year but had the hiss every now and then. But I would change an amp or something else in the set up and it would go away. Now it is there if the Reduction is on. Doesn't matter if a TT is hooked up. Gets louder as volume is turned up. Not real noticeable at volume levels I listen at. Doesn't seem to bother with music playing, but I know it's there and it bugs me. Moved it to a different system and still there. Tried all kinds of grounding changes, still there. Maybe slightly less with stock tubes than with EH6922s. Any thing I should look at?