AASTRA 4187 Plus for BusinessPhone User Guide EN - Manual (Page 80)

Settings
BusinessPhone – Dialog 4187 Plus 80
Headset Preset
This function will automatically connect Dial-by-Name calls to the
headset without pressing the headset key. By default, Headset
Preset is automatically activated when you connect a headset
to the headset terminal of the telephone. When the headset is
disconnected, the function will be automatically deactivated.
If you do not want to use Headset Preset when you use a headset
on your telephone, you have to manually deactivate the function: ²
Press.
¯
or
·
Press to navigate to the HEADSET PRESET menu.
´ ²
Press to enter the menu.
The display shows the current setting, for example:
Note: The default setting is ON. ¯
or
·
Press to toggle between ON and OFF.
´ ²
Press to save and exit.
HEADSET PRESET
ON