Dexter Romweber started Flat Duo Jets back in the mid-80s. The Chapel Hill band influenced the likes of Neko Case and Jack White. These days, Dex performs with his percussionist sister Sara Romweber (Let’s Active). The Dex Romweber Duo plays The Grey Eagle on Friday, Dec. 28. In advance, Dex talked to Xpress about documentary films, N.C. bands, creativity and his real feelings about drum-and-guitar duos.