The Sounds from Spain showcase at SXSW always offers some surprises, but this year Track Dogs really shattered some preconceived notions about the kinds of sounds that the city of Madrid brews. We had a chance to visit with Robbie and Garrett from the band, who come from the U.S.A. and Ireland, respectively. Together with another Irishman and one Englishman, they brew up highly-spirited folksy acoustic roots music with a touch of Spain in the cajón.