Carey Mulligan has revealed that the cast of Inside Llewyn Davis would have jamming sessions in between filming.
"I don't jam, but they jammed a lot. They're musicians - they just get their guitars out and start playing music. It's very enviable," she said.
Carey admitted she didn't join in with the sessions, adding: "I tap my feet on the floor and that's as much as I get involved."
John said he didn't get involved either, saying: "There was a lot of that, but not with me."
Oscar, who plays the title character - a folk singer in New York in the 60s, revealed getting to indulge in tunes was a dream come true. They worked closely with producer T-Bone Burnett and Carey's husband Marcus Mumford in choosing songs for the soundtrack.
"There was tons of jamming. There was a great week before we started shooting, where T-Bone Burnett brought us all to the last fully analogue studio in New York City and me, Marcus Mumford and Timberlake and the entire cast got together and played all this music," the 33-year-old recalled.
"It was a really amazing night. We were figuring what the soundtrack would be at the time, so there were tons of old folk songs playing."
Inside Llewyn Davis, which screened at the BFI London Film Festival, will be released on January 24, 2014.