For first-time users, the quick setup wizard allows you to set the devices you will use as your default devices.  Once set, your subsequent sessions will use the default settings you’ve selected.  To begin, choose whether you want to use your camera or not.  If so, select your camera from the drop-down.  Next, select your microphone using the microphone drop-down.  You also have the option to select your speaker.  Once you select a speaker, you can test the speaker by clicking on the play icon to the right of the internal speaker drop-down.  Once you are satisfied, confirm your selections.