Do you have a video device?
Do you even want to use a video device?
linphone seems more like a voice app to me. VoIP? Not that I'll be able to use it once it does install since I'm on dialup. But perhaps linphone.org has info on your particular issue and how to work around it.
http://linphone.org/index.php/eng/f_a_q
Some sort of SIP protocol and it looks like it defaults with video. Maybe you can ln -s /dev/null /dev/video0. Although probably not since it's might expect some sort of functionality. Perhaps rm -rf ~/.linphonerc so it will create a new one. Or modify it to disable video. man linphone? I've never used the app myself, but perhaps a place to start.