How to Make Skype Buzz
Skype allows people to make video and audio calls to each other over the Internet, with calls made between computers being free. If you want, you can set up a notification inside of Skype to make a buzzing sound whenever someone sends you a chat message or calls you.
Click "Tools," then "Options."
Click "Notifications," then click "Sounds."
Select which events for which you wish to play a sound notification by clicking them, then click on each individual event and select which sound you wish to play when it occurs.
Click "Save" to save the settings.