The actor, who appeared via video call to speak to Colbert, could not be heard through the presenter’s earpiece or on the broadcast.
Rather than cut out the three minutes of attempts to fix the audio that ensued, Colbert passed the time on camera by singing the song “Just Dropped In (To See What Condition My Condition Was In)” by Kenny Rogers and The First Edition.
As Radcliffe burst into laughter, Colbert told the actor to mime his answers to his questions, following which Radcliffe did a series of cut-throat and thumbs up gestures.
Eventually, Radcliffe provided Colbert with his phone number (scribbled on a piece of paper that producers blurred out) and the audio portion of the interview was conducted that way.
Colbert was the first late-night host to broadcast from his house in the wake of the coronavirus pandemic.
During the interview, Radcliffe discussed being the subject of a coronavirus hoax. "I've had various weird stories made up about me over the years, but none as topical as this," he said, explaining he first heard rumours were being spread that he had coronavirus when he was working on the Endgame play at London’s Old Vic theatre.
"The makeup artist said, 'You've got coronavirus.' And I said, 'What?!'" Radcliffe recalled.
"He had got a text from his niece, who apparently had just texted him, saying something to the effect of, 'That dude you're working with, he's got coronavirus.'"
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