Set manual touch tones
1
Press Menu 4-4-1-1 (Menu > Settings > Phone settings > Touch
tones > Manual touch tones).
2
Select one of the following options and press OK.
Continuous – the tone sounds for as long as you press and hold a key.
Fixed – sets the tone length to 0.1 second, regardless of how long you
press a key.
Off – turns off the tones. No tones are sent when you press a key.