why SONY Notebook VGN-BX series speakers do not work ?

     1 Please make sure your speakers are properly connected, and the volume has been raised to the level sufficient to hear the sound.
     2 Dell Latitude D820 Battery of the speakers you may not be used for computer design.
     3 If the speakers have a mute button, please set it to shut down.
     4 If the speakers have a volume control, make sure to have enough volume to hear the sound level.
     5 If there is audio cable to connect to the headphone jack, disconnect the cable connection, the use of loudspeakers attached to the speaker cable.
     6 If you are using Hp Pavilion Dv8000 Battery power, make sure that the battery is installed correctly and have sufficient power.
     7 If the speakers require external Dell Latitude d800 Battery power, make sure your speakers are connected to the power supply. For more information, please see the speakers attached to the manual.