Movies files end at 70 minutes???

Has anyone else experienced this? Since this software doesn’t play AC3 files I often have to use Visual Hub and convert them to an .avi file without the AC3 audio. When I do so and upload them to AppleTV they play fine but always end at about the 70 minute mark. On my computer the original file is the exact same size and has the entire movie. I always want the best quality so I tell Visual Hub to “go nuts”. Is there a limit as to the file size AppleTV will recognize? When I convert them they usually start in the 700mb range and come out around 2.5gigs.

When you encode files with AC3, you have to set up the audio channels this way.

As for what the Apple TV can handle, it can handle