Rane DRZH Guide D'utilisation page 7

Operation
By default, the display on DRZH will show the volume setting for the
current room (zone): Volume.
To adjust the volume, turn the knob.
You can access and adjust other settings, as well, depending on the
system DRZH is connected to.
To select another setting, push the knob. The current setting will
be shown in the display.
The adjust the current setting, turn the knob.
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