Just installed Linphone as an alternative to Skype and set up the program on both home computer and laptop to communicate with home when I am out. User IDs registered on sip.linphone.org ok.
Tried our first call today - I rang home and the programme rang at the other end, however, when the call was answered there was neither sound nor video but just a window with a green background and my own video image - and similar at the other end.
Help....!