Check the microphone and speakers currently connected by clicking Check Audio and Video

You can select which device or source to be used as your microphone and speakers
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Disable your speakers on your device

Press the Windows key and type "Sound Settings"

Click "Manage Sound Devices" and disable the default speakers on your device.

By disabling your speakers, your device will be forced to use the earphones/headset as your output device.

For Mac users, you can also check your settings to set your output device:

Go to System Preferences and click/search for "Sound"
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Click on Output and check what is selected (you may change as needed).