Yesterday i picked up a micro hdmi cable to try video for the first time. I got video but no audio. I am running 4.2.1. I checked this forum only to find these threads. Here is what I found:
No audio on my 26" Sony
Turning the audio up first made no difference
The image goes off screen
When i plugged it into the tv while the tv was set to a different input, audio still played from the TF300T speaker. As soon as i changed the tv input to hdmi, the TF300T audio went silent.
Then I tried it on my old rear projection Sony tv and audio worked.
The TF300T is definitely having trouble on some tv's - newer models???
I guess i'll report it to asus.