In order to have the best video call experience, you have to ensure that you're taking the call in an optimum environment and that your are familiar with all your device settings.

Most video conferencing systems or solutions likely have a speaker volume setting. When you are about to begin a call, try not to overdrive the volume. Remember that the higher your volume, the more potential for noise to be picked up by your microphone and re-transmitted back to the other end; this causes an unpleasant echo effect.

If you are using a monitor that has its own speakers with a video conferencing room system such as a Polycom or Cisco, the best practice is to set your monitor volume to 50% with that remote control, and then adjust the room system's volume accordingly.

When you are in a place that's not that could have a lot of background noise, consider muting yourself. Many times we are unaware of how much unintended noise is in a meeting. But don't get too comfortable with the mute button either. 

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