hey i had this problem as well whenever you go out of skype the sound of a call quits right? Im on windows eight with a desecent desktop so im not worried its me its definatley skype. If your on windows 8 like i am then by default it will use the skype app from the windows store dont use this one. to fix your problem go ahead and uninstall that skype and go to skype download on the internet not the store. Then dwonload the desktop version and it should work worked for me hope this helps and hope they fix this annoying bug.