And it keeps getting better NOT!
Ubuntu 12.04 64 bit repos contain VLC 2.01. And it plays the offending mp4 just fine, sound and all.
A fellow over at the Scientific Linux forum
seemed to offer a possible solution by compiling VLC 2.0.2 for our flavor of Linux. I added his repo to my virtual machine and upgraded VLC 2.0.2 over top of 1.1.13 from RPMForge. It seems to work but still the offending file has no sound.
Interestingly when I try the play the offending mp4 with Totem I get a message that it needs plugins for:
- MPEG-4 AAC decoder
neither of which it can find. Both of these seem to be present in VLC as I described earlier.