I hooked up the MBP 13" to my TV using an HDMI port and never could get the sound to work. Great picture, just no sound. I tried every configuration I could imagine, watched tutorials on youtube, surfed this and many other forums for answers. No joy. I even took it to the local Apple Store Genius and they used their tv and of course got it to work. Finally, someone (at Radio Shack,I was desperate) suggested using external speakers. Wow, why didn't I think of that! Works just great.