loud noises if volume under 100

I am trying to connect Volumio(RPi 3 B+) with a DAC thru USB, but only volume=100 is working; If volume under 100, then it becomes loud noises.

  • Volumio version : 2.513
  • Output Device : xCORE USB Audio 2.0
  • Mixer Type : Hardware

I’ve been tried [Mixer Type] to be Software or None, both doesn’t work either.

Any one can help ? thanks in advance !