Jeremy Corbyn claimed he watches the Queen's message at Christmas - even though he doesn't know when it is in on.
In an interview with ITV, Mr Corbyn was asked whether he sat down to watch the Queen's annual message, he said: "It's on in the morning, usually we have it on."
But he was corrected by Ms Etchingham, who told him: "It's not on in the morning. It's at three o'clock in the afternoon."
Mr Corbyn replied by saying he and his family "don't watch television very much on Christmas Day" and are often out visiting homeless shelters instead.
Pressed on whether he usually watches the monarch's public addresses, the 70-year-old said: "There is lots to do. I enjoy the presence of my family and friends around Christmas. Obviously, like everybody else does.
"And, I also visit the homeless shelter, either on Christmas Day, or the day before, to talk to, and listen to people's lives, about how they could be made better with a government that cared for them."
He also took the chance to apologies again for those who had "suffered" as a result of the anti-Semitism in his party and called the rise in racism against Jewish people "appalling".
"Anti-Semitism is a vile evil in our society. I am not a racist, in any form - I've spent my life opposing racism," he told the programme.
"And, I think the treatment of Jewish people that suffer from anti-Semitism is appalling.
"And where there's been delays by my party in instituting a process, of course, I apologise to those that suffered as a result of it."
Mr Corbyn - who has campaigned for decades for a solution for the Palestinian people - said he accepted the state of Israel had a right to exist.
The full programme - The Leader Interviews: Jeremy Corbyn - Tonight - will air on ITV at 7.30pm on Thursday.