You can change the volume level of the speakers and headphones.
Press the F3 key while holding down the Fn key to turn down the volume. Press the F4 key while holding down the Fn key to turn up the volume.
Alternatively, press the VOL (Volume) buttons on your VAIO computer to adjust the volume.
Press the F2 key while holding down the Fn key to turn off the volume of the speakers and headphones.
Press the Fn+F2 keys again to turn on the volume.
Alternatively, press the Fn+F3 or Fn+F4 keys to turn on the volume.