No, when the PP2000 is totally unplugged from the wall (and hence the neutral path which is also grounded is removed), the hum disappears. Then the whole stereo is functioning like some giant battery operated device. This is odd, since it seems to be the AC mains connection that is leading to hum. There is only one path to ground at that point, the neutral path through the AC plug. Is it possible that there is a ground loop problem within the PP2000 creating the hum, which is eliminated when there is no external reference to ground? Or what do you suggest? |
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