I've had a lot of difficulties getting my headset's mics to work with my Air. I've used the iPhone 4 packaged headset, my vmoda vibe duos, my Astrogaming A40s and my Astrogaming A*Stars. I've been able to get them all to work on rare occasions, but most of the time the external microphone will never show up in my sound settings. Is there something special I can do to make sure it always shows up?