Windows XP
Blender 32 bit version 2.68a
(Also, I don't have the XP system in front of me now, and may not be able to log in to this reporting system again as I forgot the password and somehow got in anyway without a password (from a password reset email link), but it won't let me change my password without the old one (which I don't have!). Maybe this is another bug - perhaps someone can put this where it should go for me, because this is my first time here and it's not going well so far.)
Blender BUG Description:
When rendering a video from multiple source files in the sequencer, some source *.avi files render at ridiculous playback speed, so that they finish well before their allotted time, followed by a black screen until the next source clip starts.
I don't have a blender file to attach for you, but I set up my video editing with a new install of blender, and then basically just followed the first 12 mins or so of this tutorial: https://www.youtube.com/watch?v=te9HFQVaSUE
...except I didn't bother with his imported key configuration - I just used Blender's defaults.
To create a reliable failing *.avi file, use CamStudio. I didn't let it record audio, and I think I used the first codec on the drop down list (I think it was Cinepak Codec by Radius), with a 30fps rate.
I recorded an area 1280x720. It doesn't matter how long the video is, but most of mine were at least tens of seconds long.
You just need two files. Put one on a higher channel (eg channel 3) and put the next one on a lower channel (eg channel 2), but position the second clip to start before the first clip has ended. Set the frame extents to cover all the footage, and render it. (I used H264, 1280x720, 29.97fps, MP4, with audio codec. I also had audio *.wav files in the sequencer, created by Sound Recorder, but I suspect this is irrelevant - though I haven't tested without them.) Playback in VLC should show it has ruined the second clip, and after the first clip ends, it will play the second at hyperspeed, followed by a black screen until the end of the video.
(I even had problems with trimming the END of a clip causing the issue, although I not certain whether at least one of these actually worked, so I won't put it in the "conditions" list - but it is worth a mention.)
I didn't have nearly as many issues with videos shot on an actual camera, in *.mov format. I did experience the issue with these, but it seemed more unpredictable. I found I could not trim them if I wanted to guarantee that things worked with no issues. Some could be trimmed, some could not.
I quickly learnt not to start any video clips prior to the ending of a video clip on a higher channel, if I didn't want my time wasted by Blender. (It was reliably wasting my time if I didn't follow that rule.)