Once connected to conference audio a meeting host can control his or her audio via the Audio Panel.
Opening the Audio Panel
Open the Audio Panel by clicking on the dropdown menu icon to the right of the audio icon on the top menu bar. If you're connected to the audio conference via a telephone, the audio icon is a green handset. If you're connected to the audio conference via your computer, it's a green microphone.
Audio Panel options
The Audio Panel allows you to adjust your audio level, mute your audio device, disconnect from the audio conference or switch to a different connection type (phone if your connected via computer, computer if you're connected via phone).
It also permits you to select a different microphone if more than one is enabled on your system.
Joining the audio conference
If you have not yet joined the audio conference clicking on the dropdown menu to the right of the audio icon (now a white handset) will open the Audio Wizard that walks you through the connection process. See the "Audio Wizard" article for details.