Starkey ARIES PLUS Operation Manual page 12

ON, OFF AND VOLUME CONTROL
The numbers on the control
provide an orientation for the proper
volume setting� When the control
is set at "4," the volume is at the
maximum level�
To make sounds louder, rotate the
control upward� To make sounds
softer, rotate the control downward�
The softest level is set at "1�"
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