Thanks for your response, I think hum is the best qualification for the ‘noise’ I mentioned up here. Maybe it’s possible for me to record the hum with my iPhone tonight when it’s quiet, but I think you understand what I mean and I think that’s the right classification of the ‘noise’ I hear.


#1: Ultra Dac, Roon Rock, QNAP TS-453 Pro, Meridian 857, Magnepan 20.7
#2: 818v3, DSP8000SE