If the person you are calling is unable to hear your voice, then there could be a problem with the settings of your audio device. Ensure that your microphone is not set to mute. Click on the speaker icon in the system tray and check if the "Mute" option under the Microphone section is selected.



The speaker on the other end could either be set to very low or may be turned off. However, if either party is unable to hear other audio from their PC, then there could be a problem with the speakers.

Skype automatically adjusts the audio settings of your microphone and speakers. To disable this setting, navigate to "Tools I Options" and click on "Sound devices" in the left panel. Now uncheck the option "Let Skype adjust my sound device settings". Also check that the enlisted audio devices are correct for Audio In and Out .