Panasonic KX-TG155SK Service Manual page 37

B) Vox level:
It makes easier to detect a small voice (caller) by raising the sensitivity of VOX level. Therefore, the recording of TAM is not
turned off during a detection.
1) ~ 2) are same as (A).
3) Press "5","1","1".
4) Then enter the below last digit;
5) Back to "standby" mode automatically after step 4).
Service ready
:5 1 1
CLEAR
default setting
last digit
"0"
: normal
6dB up
"1"
You can hear beep sound which is a confirmation tone.
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KX-TG155SK/KX-TGA660M