If the United Nations’ General Assembly convened at Studio 54, Ibibio Sound Machine would easily be that night’s headlining act. This octet fuses ecstatic African highlife music and pulsing disco beats with British singer Eno ­Williams’ folktales of her Nigerian heritage, which she delivers in the country’s native Ibibio tongue. The group isn’t afraid to get ­political: “Give Me a Reason,” from their March album Uyai, addresses the heartbreaking kidnapping of 276 Nigerian schoolgirls by the ­terrorist group Boko Haram in 2014. There is still a joy in Ibibio Sound Machine’s approach. “Growing up, I was around very strong and positive women,” says Williams, 43. “I wanted to write about those things. People shouldn’t be afraid or stifled.”