Recently I was given a video by a friend in AVI format that caused trouble when playing it on my Neuros OSD. When I watched the video on my laptop with mplayer, everything was fine, but when you tried to seek with the Neuros it reported a video 16 minutes in length instead of the full hour it should have been. Poking around the internet I found the following solution: Use mencoder to rebuild the AVI index, and write it out to a new copy of the video.
$ mencoder -forceidx input.avi -o output.avi -oac copy -ovc copy
$ mv output.avi input.avi
After that, the new input.avi should be playable, and seeking should work properly again.