The artist, real name Maxwell Fraser, died at his home in south London, according to the band, known for "Insomnia" and "God is a DJ".
The causes of death were not specified.
"We are heartbroken to report that Maxi Jazz passed away peacefully in his sleep last night," the band tweeted on Saturday, paying tribute to one of the founding members of Faithless in 1995.
"He was a man who changed our lives in so many ways. He gave real meaning and message to our music," the band continued, hailing a "lovely human being, who had time for everyone. and wisdom that is both deep and accessible".
Faithless rose to prominence in the mid-1990s, and enjoyed public and critical acclaim for their album "Insomnia", to the point of emerging as pioneers of dance music at the time.
The group, which counts among its other members Rollo and Sister Bliss, has released six other studio albums as well as several compilations.
Their most recent record, "All Blessed", was released in 2020.
Sister Bliss paid tribute to the artist, sharing a black and white photo of him on Twitter, sending "love to all of you who have shared our musical journey."
Reggae band UB40 meanwhile hailed a "lovely guy", recalling being on tour with Maxi Jazz & The E-Type Boys, another band of the artist, in 2017.
Hailing from Brixton, south London, he was a die-hard Crystal Palace supporter, going so far as to become the football club's associate manager in 2012.
The club took to Twitter to hail a "legendary musician" and that the team would take to the pitch on a Faithless title on Monday to pay their respects.
© 2022 AFP