Boston Terrier Rio singing to Mumford & Sons (and refusing to sing Katy Perry & Gotye)

Our dog Rio, he is a brown boston terrier and he loves mumford & sons VERY MUCH. As you see he when I played Katy Perry an Gotye he refused to sing, but the moment I put mumford back on, he begins to sing again. The day we brought him home we noticed him singing when Sigh No More played, and he would not sing to other songs. Well here we are almost 2 years later and he still digs this song.