When connecting to a classroom display, your MacBook may change your audio output settings to utilise the speakers in the Classroom Display. Alternatively it could decide to continue to send audio to your MacBook speakers, resulting in no sound coming from the display. You can quickly check or change these settings with the steps below:

1.

Open the Mission Control menu in the top right hand corner of your screen.

2.

Click on the Sound menu to open a list of audio devices.

3.

If the icon next to MacBook Speakers is highlighted blue as per the below image, this confirms that your device is using it’s in-built speakers as the audio device.

4.

To utilise the external display speakers, click on the name of the screen – BenQ RP704K in this case, however depending on the room it may be ST7502, HDFTV, DTV or similar. Generally there will only be 2 or 3 options rather than the many in the image below.

5.

If sound is still not being played through the external display you may need to adjust the volume on the display itself or room control panel.