My experience is a bit different. The amp is quiet at all volume position (with my K701 balanced with SE converter plugged in) - as long as I do NOT touch the knobs. When I have my figure on either of the knobs there is some slight hum/hiss coming to my ears (with no music playing). The loudness of this hum/hiss does not seem to relate the the volume setting. I guess this is some sort of static but here in Hong Kong we are having a very wet day so I doubt where the static comes from.
Anyway, when music starts to flow, all these don't matter any more :-)