Skype and Windows 10
If you have trouble with the sound not working when you receive Skype messages under Windows 10, there may be a simple fix.
Check the sound settings in Skype to ensure that the sound is set to use the proper speakers. Under Tools -> Options -> Audio Settings. It appears to default to digital sound, but if your computer does not have digital speakers, then you will hear nothing. Switch the setting to your regular speakers to hear the sounds again.