Article continues below advertisementHoward Stern's radio show cancelation prank has his staff very concerned, according to a new report.As retirement rumors swirl, Stern trolled listeners on September 8 alongside Andy Cohen.Article continues below advertisementHoward Stern's Prank With Andy CohenSource: The Howard Stern Show/YouTubeAndy Cohen joked he was taking over Howard Stern's SiriusXM channel. "This is, I know, not the voice that you expected to hear," Cohen said.