You can find your answer in the Owner's Manuals for any phone by looking for Resources under the "About" tab.
==>Set Keypad Volume
1. From Key Volume, scroll right or left to set the keypad volume.
2. Press the OK key to save.
==>Set Key Tone Length
From Key Length, select Normal or Long to set the length of the keypad tone.
For more details see the owner's manual at http://www.virginmobileusa.com/resources/phones/prepaid/manual/kyoceras2100.pdf
answered 2 years, 6 months ago