It happened to me with latest cm nightlies, and with all of them I had freezes and hangs. I went back to stock rom with elementalx kernel and i don't have any of these issues. I think cm overall is less stable and faster than stock rom. it's good for non nexus devices, but with nexus is better to stick to stock. I've tried other ROMs as well, nothing compares to stock in performance and stability.
Sent from my Nexus 7 using XDA Premium 4 mobile app