There is none.

Annoying or not, loud or not.
Cops had the right to arrest him for disturbing the peace.
In a courtroom, they would have done the same thing, arrested him, handcuffed him and taken him out.
They wouldn't have tried tasering him just to shut him up unless he bit, punched or kicked someone. The kid did neither.

That cop blasted him three times in a row...123. And a couple of other times. He was (in my opinion) torturing him. Using excessive force.
He could have killed him.
Whether this guy is known for his loud displays or not, the cops actions were illegal. They already had him restrained.

Maybe the cop just should have punched him in the mouth three times in a row instead while his hands were cuffed behind his back? At least the most damage he could have done were to knock out his teeth. Would that have been allright in your book Frank?