Listen to I Don't Know, But I've Been Told online. I Don't Know, But I've Been Told is an English language song and is sung by U.S. Drill Sergeant Field Recordings. I Don't Know, But I've Been Told, from the album Train Like an Olympian: 50 Cadences for a Perfect Workout, was released in the year 2012. The duration of the song is 1:51. Download English songs online from JioSaavn.