Yes that's damn annoying isn't it, specially when you're trying to get to sleep to a Siggraph presentation, and it just stops
3 mins after you've got into bed :)
I too have noticed problems with CV playback, which for me at least, seem to be worse when there are a lot of people watching, like in the week after Siggraph videos first go up :) Your 16MB connection is totally fine for even 4K video, so the problem is not likely to be your end. Unfortunately, there is also not likely to be anything you can do about it either, other than find the videos elsewhere, and/or notifying Cineversity that you're having problems, and seeing if there is anything they can do their end.
CBR