While just about everything in Marvel's "Guardians of the Galaxy" could be considered a success, there's one aspect of it director James Gunn wasn't expecting: the popularity of the soundtrack, "Awesome Mix Vol. 1."

The mix tape was a hit with everyone who watched the movie, even though at first a soundtrack wasn't commercially available. With that collection of songs leaving such a huge impression on fans of the film, Zap2it asked Gunn about the process of choosing the songs for the next "Awesome Mix," which will accompany "Guardians of the Galaxy 2."

"People keep asking me do I feel added pressure because of the movie and I'm like, 'No, I don't.' Because people liked the first movie so much. I feel a great relief because of that," he says. "The soundtrack, yeah. I'm not as confident in it being -- I didn't put songs together to be a CD. That isn't how I created the first soundtrack. I created the soundtrack to be a mix tape of Peter Quill's that told an emotional journey of his life."

At a certain point though, Gunn has to trust that what led him to find the right songs for the first movie will be true for the sequel as well.

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"I had to just let myself go and approach it in the same way," he explains. "The songs are not made to be a collection outside of that. They were made to tell a story, 'Awesome Mix Vol. 2,' what they are to Peter Quill."

What that means though, is a very different collection of songs for the "Guardians of the Galaxy Vol. 2" soundtrack.

"They're a little bit more elevated than the songs in the first movie. The songs in the first movie were something that Peter Quill's mom made for him when he was 8 years old," Gunn says. "The second one is a couple years older than that. The songs are a little bit more complex, there's diversity in the songs. There's some gigantic hits, which there weren't in the first movie, but also there's some completely obscure songs, which there aren't weren't in the first movie."

The question on many minds though is will it resonate with viewers the way the first "Awesome Mix" did? At this point, Gunn's not sure.

"I think we have something that's magical and wonderful. Will it work as a CD? I don't know, that's not really my concern," he says. "But it is my concern how it works in the movie and it works great."

"Guardians of the Galaxy Vol. 2" is in theaters May 5, 2017.