Default Call screen problem


Incoming call screen works fine, but when i answer the call, screen turns completely black only solution is to mash power button to end call. I am using Cyanogen mod 11 2014-07-29 nightly 4.4.4 . This problem came up when i was using Resurection Rom. I though that screen turns black because detectors near speaker sends the signal to the rom that phone is near my ear so it needs to go black, but no, one day phone just crashed and this happened.