I've been using 20140329 since it dropped, and chat/audio have been working great until tonight. I can hear my friends in party chat, but they sound far away and my mic is not working.
I've tried a hard reset, different controllers, nothing seems to work.
My Xbone system firmware is 1404.140331-2200. I believe this was new today, so it may have broken something.
EDIT: Titanfall ST is drifting again too. Tried with Drift Guard on and off, no difference.