BlackBerry phones have either a physical or onscreen keyboard that makes a sound when you dial a phone number or type words in one of its applications. The BlackBerry operating system has various settings for turning off keyboard, trackpad and ringer sounds. If you're using your phone in a quiet environment, you may want to turn off the keyboard's key tones.
Select "Options" on your BlackBerry's Home screen. Select "Typing and Input" and click "Keyboard" to view your keyboard settings.
Uncheck the box next to "Key Tone" to turn off the keyboard sounds.
Press your BlackBerry's "Menu" key, then select "Save" to apply the change.