In Mac, Android and iPad devices you can arrange the in/out audio levels by using the standard instruments of your device. Instead, using a PC you can open a local audio window through the main horizontal menu -> Windows -> Audio control or with the toolbar button:
PC: Audio button
This is the audio control window:
With this dialog window it is possible to adjust your local audio in a video conference.
Moving the Speaker cursor it is possible to regulate the volume of the audio received through the speakers or headphones (go to right to increase, to left for lower volume).
With the Microphone cursor it is possible to regulate the volume of your microphone (modify it if the other users note that our voice is too high or too low).
Microphone level-1 shows the percentage of volume of your voice.