znalazlem :
"*#0002*28346# code for changing volume
TX - controls how loud people will hear YOU
RX - how loud YOU can hear people
- XX dB .. +XX dB .. logarithmic scale.. negative values decrease volume, positive values amplify volume, 0 dB = “original” sound without any processing (decrease/amplification).
Works also with the ring tone volume, speakerphone volume, media player.. everything - and values are retained after soft-reset.
*"