1) Have you patched up SQL Server (and Windows)?? There were quite a few patched bugs with AGs.
2) When you set things up, did you follow the LARGE amount of gotta-do's for installation, config, testing, etc? Always On has a LOT of caveats, provisos, limitations, gotchas, etc!!!!
Best,
Kevin G. Boles
SQL Server Consultant
SQL MVP 2007-2012
TheSQLGuru on googles mail service