the day i bought my atrix (few months ago) i downloaded a movie (.avi file) and loaded it into the phone (USB mod)
and then connected it to the TV using the HDMI cable.
the interface is AWESOME and all..
but when i started the movie-there was no sound.
i reconnected it, same thing.
then i went and checked it in the phone itself- no sound.
the movie had sound on the pc but not on the phone.
i think i even tried 2 movies..
now, after i played too much with the cable, when i connect it, it enters the remote interface and then exits it. infinity. automatically enters and then exits...
so, if you are willing to help, obviously we first need to fix the remote interface problem, then maybe the sound problem..