Just a thought though, you did download the Google Video Chat application for OS X?
I just bought a new IMAC - my first. I use FaceTime with one of my daughters and the other daughter uses Google Video Chat. I used the google one when i had my PC.
Now with the IMAC FaceTime works fine. I have a problem with the Google. She can see and hear me but I can only hear her. Can't see her and remember the FaceTime works fine. I downloaded ICLOUD recently. Would that have anything to do with it?

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