Draytek Vigor2820 Series User Manual page 198

Region
Volume Gain
Vigor2820 Series User's Guide
Select the proper region which you are located. The common
settings of Caller ID Type, Dial tone, Ringing tone, Busy
tone and Congestion tone will be shown automatically on the
page. If you cannot find out a suitable one, please choose User
Defined and fill out the corresponding values for dial tone,
ringing tone, busy tone, and congestion tone by yourself for
VoIP phone.
Also, you can specify each field for your necessity. It is
recommended for you to use the default settings for VoIP
communication.
Mic Gain (1-10)/Speaker Gain (1-10) - Adjust the volume of
microphone and speaker by entering number from 1- 10. The
larger of the number, the louder the volume is.
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