Miley Cyrus and model boyfriend Justin Gaston have split after less than a year together, according to multiple reports.

The pair reportedly did the deed on Sunday before the Hannah Montana star jetted off to Savannah for a new film project.

"They have been having trouble for a while," an insider tells Us magazine.

"It's been hard for a long time since Miley has been working so much and traveling a lot."

So what part does Miley's ex-boyfriend Nick Jonas play in all of this?

Sources say he "was not the reason for the split, but they have been spending time together."

The source adds: "Miley and Nick are working on a couple different projects together. Justin has been a little jealous of that."  

Specifically, Nick and Miley hooked up to record a break-up song together called Before the Storm.

Nick tells Twist how the unlikely collaboration came about: “There’s two versions of the song basically, one that was written just for our record that we sang originally.

"And then I played it for Miley and we realized that if we just changed the lyrics a bit, we could make it more of our story, kind of share that side of us, and it could be great.

"So, we did. She came in and she and I sat down at the piano and just worked on lyrics a bit, tweaked it up, and it turned out great!”

See Miley & Justin below