I thought this might be an issue with hardware originally but it seems to actually be an issue with the OS itself. Basically whats going on is whenever I try to place or accept a call on my Mac Pro, the other person cannot hear me. Thank to AppleCare, we were able to get it going for a little while but after about 3 hours it stopped working again and I get no outbound audio. We tried going into the root user and renaming my Application Support folder (in the home directory) so the system would automatically regenerate the folder. That worked surprisingly and it was functional until this morning when I went to make a phone call and again, same issue. I called back and another advisor told me to delete the cache folder (~/Library/Caches) which worked, again, until a few hours later when I placed a call and no one on the other end could hear me. It is worth noting that System Prefs picks up my mic (just standard EarPods) and I can record an audio track in QuickTime with no problem. Heck, I can even make a FaceTime Audio call it works fine. Whenever I try to make a continuity call however, it doesn't work. Does anyone have any ideas what to try? I am at my whits-end here and nothing is working.