Why my phone lags when my nofications notifies me nothing?

[AC Question]

I have a problem my phone suddenly lags when my notification notifies me
You know when something notifies you it appears in the top of your screen with black background in my situation it notifies me nothing. When i play games or watch videos when it happens it lags or stops the video Im watching. Its like an aftershock in my phone I don't know what to do please help me on my problem thank you very much

 

[B. Diddy]

Welcome to Android Central! Which phone? Does the notification tone sound like your default tone, or is it different? Does this happen if you turn off NFC?