Marvo MH01 Manuel D'utilisation page 7

Use
Headset
Use the knob on the headset to control the volume.
Mouse
Press the buttons below the scroll wheel to change the
sensitivity according to predefined DPI steps.
Mouse Driver Use
Key Setting
Select "Mode A" or "Mode B" tab and set user-defined
function of each key as following graph. 1 for Left Click, 2 for
Right Click, 3 for Mid click, 4 for forward, 5 for backward, 6
for DPI Loop is kept as default.
One click the key you want to set then chose a new
functions. Click "Apply" to save the setting.
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