How did you determine it was that application?
I'm not running that application, and I don't use HDMI. But it makes me wonder if another app I have is causing the problem.
I actually fixed my problem simply by unplugging the usb and replugging it in. I am so used to having it plugged in all the time this never came to mind at first after installing Yosemite. Hope this fixes it for most!
I think this might be an actual issue with Yosemite and not just limited to hacks.
I tried this:
'sudo killall coreaudiod'
and afterwards the calls appeared to be working - not sure if this is something I will have to do every time FaceTime is reopened or the hack is restarted....
i fixed well a least my problem this is how , maybe it might work for you too. i plug my camera went to utilities , audio midi setup , look for your camera and change format from 16,000 to 32,000 and now no more chipmunks i have called 5 different person and no problem in and out perfect crystal clear audio i hope this help good luck