Horrible Bug

This happened because you accidentally committed to the run instead of the pass... When you push the left trigger and hold up on the right stick you commit to the pass which is suggested on downs you know are passing downs. your CB's jumped up expecting
run letting the WR's run by them... It's not a glitch...

You would think backing coverage off would work but it doesn't. I've had this happen to me many times in the same situation as the OP. Didn't matter if i was playing man or zone. For some reaason once or twice a game Wr's are able to get behind the secondary
with absolutely nobody around. Now at first i thought it was me but it's even happened while i played prevent and 3 deep man. No clue why it happens but it does.

I have never had this happen to me. Try backing off coverage

people still say "just saying"?

My point was that he would have to be making that mistake over and over for this to happen consistently which I doubt. But yes, committing to pass would help.

That's why you got to take advantage of the "commit to pass" option and he won't be having this problem... Also if you don't get to the QB quick enough especially when playing a zone defense you'll usually leave yourself wide open for something disastrous
just like in real football... Cover 4 get's exposed by overloads and streaks all the time especially when the QB doesn't have a pass rush to worry about... simple football knowledge... just saying..