Another natural and easy task in Lync 2013 is making calls. Whether you want to make audio calls or video calls, both are equally simple to do. Before you can make a video call, of course, you’ll need a web camera connected to your computer. You’ll be able to determine whether your contacts are able to participate in a video call because you will see Video Capable listed in the contact information to the right of the contact name.
After installing your audio device hardware on your system, in the Lync window, click the Options button.
The Lync – Options dialog box opens.
In the categories pane on the left, click Audio Device.
Use the sliders to adjust the volumes for Speaker, Microphone, ...