The Maroon 5 rocker has been dating Victoria's Secret Angel Behati Prinsloo since June last year
Although they were thought to be getting on well, it's now been claimed they are experiencing a rough patch.
Speculation started after Adam decided against taking Behati to the Grammy Awards in Los Angeles earlier this month, instead opting for his mother to be his date.
Rumours of an imminent break-up have now intensified after the group performed at Madison Square Garden on Saturday and the model was nowhere to be seen.
"We’re told that while Prinsloo was a no-show for the band’s concert at Madison Square Garden on Saturday, they did meet up afterward," adds New York Post.
Neither Adam nor Behati's representatives have commented on the claims.
News of the couple's relationship woes comes not long after it was claimed Adam's family were encouraging him to pop the question.
His parents reportedly feel the 23-year-old model is the perfect choice for their 33-year-old son and would love to see him settle down.
"Adam's mom Patsy and his dad Fred would like nothing better than for him to marry Behati and have some gorgeous-looking kids," an insider said.
"They think he would make a great dad so they've been nudging him towards the altar. They feel he's sowed his wild oats and it's time for him to raise a family."
It's a sentiment which seems to be echoed by Behati's family, with her mother calling the rock star a "fine man" during an interview late last year.
Adam dated Victoria's Secret model Anne Vyalitsyna before his romance with Behati and has been linked to Paris Hilton and Lindsay Lohan in the past.