Is it my imagination, or . . . . (Volume variation)

Installed my new Nucleus, coming from a Mac Mini, with first playback last night. So far, so good. I need a little more time with it before I write my actual review. But here is an early impression.

Playing my 2.0 files, through same USB cable to the same DAC, I see I am turning the volume from my pre/pro and power amp to a higher level than before.

Normal volume on the pre/pro was 27 - 24. Last night, to reach the same volume level, I was operating and 24 - 19. The only difference in the system was the Nucleus.

Any reasons why this is happening?

It is fine with me, I am just curious.

I bet your Mac’s mixer was amplifying the audio. Did you have exclusive mode set on the Mac?

Roon on Linux is always in exclusive mode, no mixers anywhere. Nucleus is Linux based. It’s easy to get this wrong on the Mac, but impossible on Linux or Nucleus.

That could well be the answer.

And I know that Nucleus runs on Linux.

It is no big deal, but I was/am curious about such things.