As the live semi-final began, St Patrick’s Junior Choir Drumgreenagh took to the stage but could not hear their track in the studio.
Broadcasting to the nation, the presenting pair quickly halted the show and allowed the choir to start again.
Rushing on stage, Ant said: “Hang on. Two secs. Everything okay? Everything okay?”
Dec grabbed the choirmaster’s hands and calmly added: “We’re going to just stop it there. We’ve had a few technical problems.”
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We’re going to just stop it there. We’ve had a few technical problems
As the track played with the children’s voices, Ant quickly said: “Hold on, hold on, hold on.”
One viewer tweeted: “Well Ant and Dec creeping back on stage to halt the choir was odd. #BGT @BGT.”
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“Technical issues on the first live show, brilliant #BGT,” posted another as a third said: “Oops ahaha, poor Ant and Dec #BGT.”
Other fans of the show were not happy to see that the choir was seemingly “miming” after singing was heard on the track as the choir stood with their lips sealed.
One viewer tweeted: “Britain's Got Talent shown up that those kids were miming – backing track came in after Ant and Dec stopped them singing. #BGT.”
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“They're miming when Ant and Dec walked on the track played with singing but the kids weren't singing #BGT,” posted another.
A third added: “Poor kids that was awkward they recovered well done to ant and Dec too. #BGT.”
Following the performance, Ant added: “A bit of a stage issue, they couldn't hear the track, so we let them start again.”