When you are taking a piss while simultaneously attempting to carry on a conversation with someone outside the general vicinity of the bathroom and the noise of your urinary stream making contact with the toilet water muffles the noise of the out-of-bathroom correspondent's dialogue.
Man taking piss's friend - "Hey Mike, get out here. This football game is turning into a real barn burner."

Man taking piss - "I'm stream deaf bro! I cant hear you!"
by BK347 October 28, 2010
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