TM-250U
In case of macOS
1.
From the Finder menu press Go -> Utilities -> Audio MIDI Setup
2.
Open the Audio Devices window and select “TASCAM TM-250U 2”
and then click on the Input tab.
3.
Add a check in the THRU column (marked in red in the image
below) and adjust the direct monitor volume using the sliders
(marked in yellow).
4.
To adjust the direct monitor volume and the computer’s playback
volume select “TASCAM TM-250U 1”. Click on the Output tab, and
move the sliders (mark in green).
You can also adjust the entire volume by clicking the speaker icon
on the menu bar.
To adjust the entire volume during live streams, etc. we recommend
using the volume knob on the unit.