At what point do you acknowledge fans/parents?

[Adam]

It's obvious that your concentration was affected. The tolerance level for this is going to vary by official. Some have just never experienced this level of behavior, some have just never heard it because they legitimately tune it out during a game. There's nothing that says you should have to take the abuse, just because some refs can tune it out.

I wouldn't address them personally, though. Stop the game, get game management to deal with it. They will deal with the problem. If they were sitting near them, they should have dealt with it already.