Check that you have not turned off the sound from the application settings menu. Check that your device is not in silent mode.
- How do I set up and sign in to Skype on my Nokia Lumia phone?
- Can I make Skype calls using my Lumia phone?
- Why does my Lumia only show phone number of caller or SMS sender, although the contact name is listed in People hub?
- How do I configure my number to be private when I call someone on my Lumia phone?
- How can I divert incoming calls on my Nokia Lumia phone?