Dale, I think I'm about to reconsider my position on the dampers!!! I was striking G3, which has been one of the more offensive notes, while standing on the left side of the keyboard and I tried to listen where the hiss/buzz was coming from and I realized it was closer to the bottom end of the keyboard rather than near the note. I pushed down the bass dampers fairly hard with my left hand, holding that position for a couple of seconds, and proceeded to move up the range of dampers, doing the same thing until I got to G3. When I was done...NO MORE HISS/BUZZ!! Apparently when I had attempted to mute the dampers previously I wasn't applying enough downward force to the damper heads, which down begs the question...was it the felts or something else (downward pressure on the stings or loose damper heads)?