Rock band TRAX has made a successful comeback with their first mini-album and title track Let You Go. The music video for the song featured fellow SM Entertainment members Victoria of f(x) and Super Junior's Heechul. SM family is definitely staying tight knit with�Seohyun of SNSD making an appearance with TRAX on Music Bank this evening. It's quite a surprise to see Seohyun on stage, let alone watching her playing the piano oh so gracefully. What with SNSD's explosive comeback with Oh!, you'd think the girl would be a bit tired. But nevertheless it was another great performance on TRAX's part, and the addition of Seohyun only gave us more reason to watch. http://www.youtube.com/watch?v=frWpC3Xrw4c