When the contact you're speaking to on Skype can't hear your audio, you may not know if the problem is on your end or hers. To help you determine if your microphone is working correctly, Skype includes a service known as Echo that records your voice and plays it back to you. To use this service, you must have Echo in your list of contacts. If it's not in your list, you can add it like you would any other contact.
Open Skype and log in to your account.
Click "Directory" near the bottom of the Skype window.
Type "echo123" in the search box under "Find People" in the directory window and click "Search." The user name "echo123" is the user name associated with the Echo service.
Click on "echo123" in the search results and then click "Add Contact."
Click "OK" to send an invite to the contact. Your invite will instantly be accepted and the contact "Echo" will appear on your contact list.
When you search for the user name "echo 123," many similar user names appear in the search results. Add only the correct, official user name as a contact and not a similar one.