Goldman Sachs CEO David Solomon isn't your average C-suite executive. Yes, he made $23 million last year, but since taking the helm at the investment bank from Lloyd Blankfein in October 2018, he's been eschewing Wall Street's stuffy ways.

Fifty-seven-year-old Solomon, for instance, is known as "D-Sol" on weekends, when he performs his side gig as a classic rock DJ at nightclubs in New York City, Miami and the Bahamas (think Guns N' Roses and The White Stripes).

Solomon also rides the New York City subway to work and prefers to fetch his own coffee at the office.

"I mean, why wouldn't you take the subway?" Solomon told Fortune recently. "No, seriously. It's quicker and more efficient. You know, the mayor of New York [City, Bill de Blasio] can take the subway. Why can't the CEO of Goldman Sachs?"

(In reality, while de Blasio sometimes rides the subway as a promotional event, he typically takes a private car to work, and infamously, to the gym, because of his hectic schedule, he says.)

According to Fortune, certain Goldman Sachs' board members are unhappy with the idea Solomon on the subway. But that doesn't bother him. Neither does the fact that his DJ persona has become fodder for the media, at least not anymore.

Solomon was first outed as DJ D-Sol by The New York Times in 2017 when he was a co-president at Goldman Sachs and in the midst of his campaign to be named CEO. Solomon said some of his associates urged him to hang up his headphones if he got the job, and he himself felt anxious that the public wouldn't take him seriously.