"Ignore the time thing and tell him his behavior is inappropriate."
R&R: This is not your best choice!. As you try to point out his inappropriate behavior, he will defend by adamantly insisting that you are over the time allotted. We suggest you deal with his valid grievance first.
YOU: I knew that. I just wanted to see if you were going to do something funny! What's the matter? (Sarcastically) Run out of jokes?
R&R: What's that supposed to mean?
YOU: Nothing. Don't get all emotional. Can't you take a joke?
Ten Types 
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