Just weeks after Woman's Day revealed Guy Sebastian's stylist wife Jules was growing increasingly tired of the constant chatter about her husband's short-lived romance with Delta Goodrem, the ladies have come face-to-face at a frosty dinner party.
Celebrating Boy George's 58th birthday in Sydney last week, an insider reveals that Delta, 34, and Jules, 37, allegedly got into a war of words in front of their partners, closest mutual friends and The Voice production crew.
"One too many champagnes later, it just became all too much," says the insider.
The pair are said to have exchanged a few barbed digs about Guy's whirlwind romance with Delta, before they awkwardly laughed it off.
"Jules tries her best to keep her cool, but she won't have it rubbed in her face," the source explains.
WATCH: They've been spilling all their secrets! Relive the moment Guy Sebastian and Delta Goodrem shared details of their romance on The Voice Story continues after video...
At one point, Delta's fellow Voice coach Kelly Rowland, 38, even weighed into the awkward back and forth.
"Kelly jumped straight to Delta's defence. She wasn't going to let her take all the blame," adds the source, a move which was said to have left 37-year-old Guy fuming.
"It's hard enough being the new kid on set, but when you're caught in the middle, it makes things even harder," says the insider, before revealing Guy and Jules were put off by Kelly's defensive attitude.
As if things weren't tense enough, the party insider explains that The Voice's executive producer Leigh Aramberri was rubbing Delta's long-term boyfriend Matthew Copley the wrong way all night!
"Leigh and Delta were up to their usually flirty banter," reveals another insider, adding the pair have been close friends for years.
"Between the inside jokes and constant giggling, Matthew felt like the third wheel! He was ready to walk at one stage."
The strained dinner comes just weeks after a source revealed that muso Matt was intimidated by the co-workers' bond.
"He's always supportive of Delta and her career, but he's no fool – he knows she's a catch," an on-set spy told Woman's Day after it was revealed Leigh might have tried to have Matthew kept off set.
After an intense night out with Delta's colleagues, Matt might just skip The Voice Christmas party. The insider tells Woman's Day that by the end of the night, Delta and her man ended up in a heated conversation of their own.
"There was a lot of negative energy in the room, and it eventually got the better of them," says the source, adding that while the couple have a solid relationship, the guitarist is still finding his feet with Delta's famous friends.