Jessica Mauboy left fans puzzled when she was no-show at the Melbourne Cup in 2015.

Just minutes before she was due to perform the national anthem, the singer puled out and she has now revealed exactly what happened.

The 27-year-old has told Anh Do on his show Brush With Fame, that ‘'I wouldn't say it was a panic attack. It was more… I definitely felt trapped.' 

On the show, the comedian will quiz the singer on her cancelled performance and Jess reveals all, continuing to say 'I just felt a really bad energy… it was the people I didn't connect with,' she tells Anh.

It has been reported previously that she cancelled her appearance as she was unhappy with her choice of footwear but it is not denied or confirmed in a promotional clip of the show.

She has however said that was one of the most intense experiences ever, saying 'When you just fall into the wrong hands and it's not where you want to be, and so respectfully for myself I wanted to stay true to that and not be a part of it at all,' she explains.

'For the first time, it was something that I could say no... And that was just coming from a place of being real, and being real to myself,' she adds. 

Jessica Mauboy's episode on Anh Do's Brush With Fame appears on the ABC on Wednesday, April 12th from 8pm