Indie-pop darlings the xx — whose ambient stylings somehow manage to double as a musical aphrodisiac or a sleep aid, depending on your mood — have been relatively quiet since the release of their last album, 2012’s chart-topping Coexist. But the London trio are now officially back after a four-year hiatus to announce that their third album, I See You, will be released on January 13, and they accompanied the news by releasing the leading track from the album, “On Hold.” (Listen closely. Does it sound vaguely Hall and Oates-y to you? That’s because they sampled “I Can’t Go for That (No Can Do)” for the song. Romy Croft, Oliver Sim, and Jamie xx have never sounded so … upbeat! For them, anyway.