All-female band Haim say they fired an agent after discovering they were paid just a tenth of the amount of a male artist on the same bill at a festival.
The US rock group – made up of sisters Este, Danielle and Alana – called the pay gap "insane".
The sisters told Grazia: "We had been told that our fee was very low because you played at the festival in the hope you'd get played on the radio.
"We didn't think twice about it, but we later found out that someone was getting paid 10 times more than us. And because of that we fired our agent."
The Grammy-nominated group called the disparity of pay "f****d up", but did not name the festival nor the male artist.
Since the success of their 2013 album Days Are Gone, which reached number one in the UK album charts, the band have played festivals including Glastonbury and Coachella.
Drawing favourable comparisons with 1970s band Fleetwood Mac, the sisters have rejected the label "girl band" and say they want to be recognised simply as musicians.
Talking about sexism and prejudice they have faced during their career, the sisters told the magazine that many people struggle to accept that they play their own instruments and write their own songs.
Alana, the youngest of the sisters, said: "I still get so many people asking me, 'So who really writes your songs?'
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"A lot of people automatically accept the fact that an all-male band writes their own songs, but when they see an all-woman band, they're like, 'Oh there must be a man behind it, fuelling their fire'."
Haim are currently in the UK as part of their world tour.