It seems that when you drop a 24p 72mbps clip into Sony Vegas, the video is about 5 times longer than the audio, and everything beyond the audio is a still of the last frame. This only happens at 24p 72mbps, the other codecs work correctly. Same on 3 version of Vegas (10 through 12) on 2 computers, it didn't happen in After Effects. Also posted on GH3 forum, screen shot there.