Longshine LCS-8156C1 - Manual (Page 190)

AT Commands for CX930xx Modem Reference Manual
5-26 Conexant 102752B
+VGS - Speaker Gain
This command causes the modem to set the speaker gain of the speakerphone function.
Syntax
+VGS=
Defined Values
Decimal number between 0 and 255 corresponding to the gain.
Reporting Current or Selected Values
Command: +VGS?
Response:
Example: 128 For the default setting.
Reporting Supported Range of Parameter Values
Command: +VGS=?
Response: range
Example: 0-255
Result Codes
OK = 0-255.
ERROR Otherwise, or if not in Voice Mode with speakerphone
enabled (+VSP=1).