Okay, things just got even weirder!
The problem has been replicated on an older, albeit different, machine (1.06GHz Athlon, 384MB RAM). The glitch is again appearing with the same exact regularity at every 9 minutes and 26 seconds in the video(s).
I then transferred the raw avi file from my Windows machine to my Linux box in an attempt to test a compression on that box. The entire file transferred over successfully (roughly 36 minutes long). VLC plays the video fine and indicates the correct duration of 36 minutes. However, another player (Totem to be exact) registers the video as only being 9:26 in length!
Now I’m starting to think it’s a problem with the exported avi…