What you need to know about the presidential debate mute button

Debate microphone will be muted during parts of the event

During the September debate, US President Donald Trump constantly interrupted Democratic candidate Joe Biden, leading to a series of chaotic exchanges in which both men talked over each other.

So the nonpartisan commission that oversees US presidential debates announce a new measure to help moderators "maintain order" - muted microphones.

This time, each candidate's audio feed will at times be cut while the other is speaking.

The debate moderator, NBC News' Kristen Welker, will ask questions. Afterwards both of the candidates will have two minutes to answer - with no interruptions.

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Though that doesn't mean the debate will necessarily go smoothly.

How will the mute button work?

Once Mr Biden begins to speak, Mr Trump's audio feed will be cut. This will not be done by the moderator, though. Instead, a member of the production crew who works for the Commission on Presidential Debates will be responsible for turning off Trump's microphone.

The same rule will be in place for Mr Biden. When Mr Trump speaks, Mr Biden will be muted. Officials who work for the commission are hoping these new rules will allow for a more civilised exchange of views.

In the end, the debate will allow time for the candidates to argue.

After each of them answers the moderators' questions without being interrupted, the mute-button rule will be set aside. Then the candidates will have a chance to speak with each other in a freestyle manner - with both mics on.

What has been the reaction?

Bill Stepien, the president's campaign manager, has objected, saying the rules are part of the commission's "pro-Biden antics".

Yet others applaud the effort. Richard Stengel, who served as the undersecretary of state for public diplomacy during the Obama White House, loves the idea.

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"In the case of Donald Trump, you have an adult male who has no impulse control. A mute button is a form of external impulse control," says Stengel, the author of a book called You're Too Kind: A Brief History of Flattery. "I think it's fine."

TV show hosts have made jokes about it, with The Late Show's Stephen Colbert quipping: "while we're at it, how about a fast-forward button? Just zip straight to November third" - Election Day.

The commission has said that "after discussions with both campaigns" it realises that "neither campaign may be totally satisfied" with the new measure.

But "we are comfortable that these actions strike the right balance and that they are in the interest of the American people, for whom thesedebates are held", it said earlier this week.

Still, many say the mute button is a waste of time: Trump could get his points across regardless, including through facial expressions.

Besides, the president's supporters say he is not the one who should be cut off.

Scott Pio, a software engineer who lives in Sterling, Virginia, says the candidates should speak and that others should step aside.

"I wish the moderators would mute themselves," Mr Pio says. "It is a debate. There is no reason for the moderator to interject their opinions."