As autumn begins, the later summer chamber music festival recordings are trickling into Classical MPR. In this week's Regional Spotlight are three all-star performers, concertmaster and principal cello of the Minnesota Orchestra, Erin Keefe and Tony Ross with pianist, Ester Wang. Mozart's Piano Trio, K.542 sings in their hands. From an August 23 performance at the Bridge Chamber Music Festival in Northfield comes this elegant, yet profound sounding, piece.