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Click on the hand icon again
Click Cancel Request
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Change Camera or Microphone
Click the ‘More' button in the lower left corner to the right of the share icon.
Click settings.
Select Audio or Video.
Choose the sources from the dropdowns you would like to use.
Click the ‘SAVE’ button to accept your changes.
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Mute individual speaker
Right-Click inside the speaker's live view box
Click 'show controls'
Click the volume icon to mute speaker
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