PS3 H.264 Video Lag

[OfficerHalf]

I'm trying to watch a movie on my PS3. I'm a little out of my element - codecs, wrappers, containers etc. confuse me, it's just not my department. I tried putting the 2gb file on my flash drive and sticking it in the usb port on my PS3. I browsed to the file just fine and tried to play it. I get a black screen and a little play icon at the bottom left like its playing, but nothing happens. I can skip ahead to get a frame of video, but it freezes there, the audio plays for a sec but not in sync with that frame.

The file plays just fine on my PC. (VLC, Zune, QuickTime)

It's, according to the file, (i didn't rip/encode this): 720p H.264 mp4 file. I googled to my best ability, but found nothing. People were having problems streaming H.264 files to their PS3s, but not using a usb drive.

Help?

 

[OfficerHalf]

For some reason, the file plays fine on my girlfriends fat PS3, but not on my PS3 slim. Which really solves this problem since I wanted to watch the movie with her.