The Duchess of Cornwall's efforts to get into the festive spirit don't seem to have met with everyone's approval.
When Camilla joined carol singers in a London shopping centre a man from the city council approached her to say she was making too much noise.
"You're singing too loud, you're making too many decibels – I don't want any more singing," he told her.
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What happened next was even more shocking. The scrooge then launched into a version of La Donna e Mobile from Verdi’s Rigoletto, prompting the Duchess, who by now had realised the joke was on her, to burst out laughing.
The party-pooping 'official' turned out to be Howard Ellis from the tenor group Incognito.
Around 500 shoppers witnessed the fun when Camilla turned on the lights at Burlington Shopping Arcade.
The evening was expected to raise at least £10,000 for the DecAid charity, a national appeal for service charities that help current and former members of the Armed Forces who served in Afghanistan and their families.
Prince Charles' wife also donated a bottle of Champagne and cut-glass Champagne flutes from their Highgrove estate to a raffle.
She told the crowd: "I'm a very proud patron of DecAid – young people doing their finest.
"What a wonderful example of the youth of this country. If more people followed their example we would be in a better place."