OK, picture the scene: The 32-year-old BBC Radio 1 presenter was hosting a Christmas edition of the Live Lounge with special guests Ricky Gervais, Jamie Oliver, and Cheryl Cole.
While Wizzard's I Wish It Could Be Christmas Every Day was playing, a rogue microphone was left on and online live-feed listeners heard Fearne say to Cheryl: "No swearing and don't make any w***** gestures because people will see them on the webcam."
Note she had to say it to Cheryl Cole.
Once Fearne was informed of the gaffe, she told the listeners listeners: "We might have heard some bad language on the radio because one of the mics was still faded up in the kitchen." They probably have mics in the jacks 'n all.
That wasn't the most offensive thing to happen to their audience during the show, however, as Nick Grimshaw wore a Sexy Santa red minidress for a round of DJ Scott Mills' innuendo bingo. Many may have preferred to have been treated to the sight of a naughty hand signal courtesy of Cole instead.
For the occasion, Fearne opted for a baggy red Christmas jumper featuring Rudolph wearing a Santa beard. So, obviously this picture is from last Christmas.