Are you trying to play a video to your class, but there is no sound? The problem might be the HDMI cable that you are using to connect your computer to the projector/interactive display. HDMI cables are made to carry both image and sound. So, by default, when you connect an HDMI cable, your computer thinks it should redirect sound from your computer to the output device. If the output is a projector or other device that doesn’t have speakers, you are losing sound.
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