no audio on third parties who FaceTime me, help!

Hi all. I've had two guys try to call me on FaceTime, and I wanted to use the Mac Mini over here to do the FaceTiming, so I answered, and I even asked Siri to do it for me. However, audio is broken and the parties I've FaceTimed can't hear me, or they can but I can't hear them. What should I do to fix this problem? Let me say I've checked my input and output sounds, checked on Skype, did a test call with Skype, and Skype works. But FaceTime? What in the world is wrong with FaceTime? I don't know if it's a Voiceover thing or it's an audio issue, but this is rather important, and I don't know where to go or what to do to fix this problem because the settings are set up the way I have to set them up.
Also, every time I get a FaceTime call, especially if my Mac is awake, Voiceover gets messed up. It will stop navigating lists, text, and many other things properly unless I toggle it off and back on, annoying. Thanks for the help in advance.
Beth