Had a very bad interview for PhD ahead of Spring 2016. I agreed with the professors to do a skype interview. had already set up everything on my computer and possible questions and answers. was expecting everything to go smoothly. But the day of the interview, skype blanked out globally (sometime in October 2015) for a few hours.
When time for the interview came, I got so disoriented and worried about what to do. Interviewing committee members then asked me if I could use phone instead and I did. I lost my bearing in the first 15 minutes of the phone interview but caught up later on, by then was too late, blabbed a lot in the first few minutes.
If possible, I'll advise you to prepared for the worst before an interview. I'm having some other interviews coming up again in a weeks, I'll try my best to be there physically. I think that works better for me,