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Have speakers test their Microphone by talking with you. To troubleshoot see People have trouble hearing me.
Have speakers test their Camera by turning it on. To troubleshoot see My camera doesn't work.
Ask if they’ll be sharing their screen, then check Screenshare. If there are issues, see Screen sharing in a multiple monitor environment or Screen sharing in a single monitor environment
If applicable, make sure they know how to share their screen with sound.
If they need to leave the screen, show them how: More > Leave > Continue Watching
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