fielders yelling

[Umpteenth]

I have to ask, because you have brought this up before - the fact that you play and you umpire. Are you asking from the perspective of officiating a game, or are you trying to get someone here to tell you what you can get away with?

If you are officiating, you should be able to make the judgment call as to whether or not a batter was impeded by the verbal or physical action of a defensive player. If you cannot make that judgment, perhaps you should not be officiating.

If you are asking from the perspective of a player, then be prepared to be called for Obstruction or USC at some point, when you have pushed too many buttons.