Classroom Audio Troubleshooting



This page is here to provide instruction when audio is not working in a classroom.

Here are a list of items to review when audio is not working in a classroom when trying to present. 

  • Check your physical connections. (3.5mm audio jack plugged into the laptop when using VGA for video, HDMI carries both audio and video)


    Image ot a VGA connector and a 3.5mm headphone connector.
    Image of a HDMI cable connector.
  • Check your selected input on either the SmartBox or Extron controller. (HDMI, VGA, Computer, etc. should match the cable(s) that you have connected)


  • When using a classroom with a SmartBox, look on the lower left corner of the SmartBox and check the amplifier emergency-power-off switch. It should be turned ON (The position shown). 





  • Check your sound settings on your laptop.

    • On a Windows 10 laptop, click the Speaker Icon in the taskbar and choose the appropriate audio output. 

      Audio over HDMI Connections with appear as Extron HDMI, ExtronScalerD, or the model number of the installed NEC Projector in the room. (NEC Model Number shown)




      Analog Audio connections when using VGA appear as shown below. 




    • On a Windows 11 laptop, click the Speaker Icon in the taskbar, then click the audio output selection button next to the volume slider, and choose the appropriate audio output. 

      Audio over HDMI Connections with appear as Extron HDMI, ExtronScalerD, or the model number of the installed NEC Projector in the room. (NEC Model Number shown)




       Analog Audio connections when using VGA appear as shown below. 





    • On a MacOS laptop, click the control center icon in the upper right corner of the taskbar and choose the appropriate audio output. 

      Audio over HDMI Connections with appear as Extron HDMI, ExtronScalerD, or the model number of the installed NEC Projector in the room.




      Analog Audio connections when using VGA appear as shown below.






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