Make sure:

• The speaker set is properly connected to the power supply and switched on.
• For the speaker set comes with USB cable and 3.5mm audio cable. BOTH USB cable and 3.5mm audio cable are connected properly.
  The USB connection is used for power transfer while the 3.5mm audio connection is for audio signal transfer.
  Tip: Never unplug the USB plug while the speaker is working.
   
  
  
• Follow the steps below to adjust the settings in the computer:
  1. Go to “Start”→"Settings” →"Control Panel” →"Sounds and Audio Devices”.
  2. In the pop-up box, make sure:
     • The box for “Mute” is left blank.
     • The device volume is set to an audible level.
        
       
       
  3. Click "Advanced".
     • Uncheck all ‘Mute’ boxes.
     • Put all volume sliders on high.
        
       
       
• If the problem persists, verify that the speaker set is not faulty following the steps below:
  1. Connect the speaker set to another audio device, such as an MP3 player.
  2. Play an audio file on your player.

If the file can be played through the speaker set, the speaker set is working.

• A reason of having no sound from the speaker set when it is connected to the computer may be a faulty sound card of the computer. To check the status of the sound card, follow the steps below:
  1. Insert the green connector of the speaker set into the LINE OUT socket (i.e., the socket with a symbol that has an arrow coming out from the center of the circle) of the computer.
      
     
     
  2. Go to “Start” →"Settings” →"Control Panel” →"System” →"Hardware” →"Device Manager”.
      
     
     
  3. Under Sound, video and game controllers, check whether there is any yellow exclamation mark beside the device names.
     If so, there might be errors with the sound card and its driver might need to be reinstalled.