Looks like you only did a dirty flash and didn't factory reset. That could be a reason. Dirty flashes aren't always 100% and it's why the dev recomends clean flashing by factory resetting within recovery, and wiping cache, dalvik cache, and system. Try that and see if it takes.
Site Rules/Guidelines / Meet the Team
If something needs attention, Report
If someone helped you, hit
to show it.
Current Devices: Nexus 5, HP 14 Chromebook (Data Enabled), Google Glass, (2013) LTE Nexus 7, Chromecast
Retired: Samsung Fascinate, Droid Charge, Galaxy Nexus, (2012) WiFi Nexus 7, Asus TF700, Nexus 4, Logitech Revue