To change your settings, in Skype Preview select the Settings button towards the bottom left of the window.
Under Notification Settings you can customize the following:
- Turn Instant messaging On or Off.
- Select who can send you Instant messages, Anyone or Contacts only.
- Turn incoming calls On or Off.
- Turn Play sound for incoming IM (Instant messages) in recent chat On or Off.
- Turn Play sound for incoming IM in current chat On or Off.