Default Proximity Sensor and unlock screen Issues during call on Kit Kat

Hello. During conversations I often unable to unlock the screen to hangup call or make other actions. Have someone experience same issue? Normally the screen should unlocked by double pressing on power button, right? Sometimes it takes to press 5-6 times before screen appear, it is normal? I experienced such issue on 4.3 and 4.4 with full wipes. Thanks in advance.