I know the discussion is old, sorry to raise the topic, just to make it clear, I have one of the first versions of the e30, said with "polarity defect", I put it receiving coaxial via a marantz cd4300 playing the amplifier, and the Marantz connected directly to the amplifier, playing a CD with polarity test, in short, changing the keys on the amplifier, I was never able to differentiate one from the other, that is, either I cannot differentiate because it makes no difference or Marantz also has the inverted polarity, in short, the e30 is to speculate with or without a polarity defect, it is worth much more than it cost me.