I connects my Xoom tablet to my HD TV using a Micro HDMI. After I plug Xoom in the TV, I have no sound coming out of the tablet, such as a movie app, stock music player. The images are fine do. The sound comes back if I unplug the cable.
You can try this temp fix. Taking a 3.5mm audio cable and plug it into the head phone jack of the Xoom and the other end into the headphone jack of the TV. Works for me.