I've had this problem, well....pretty much since I got my new motherboard well over 6 months ago.
Videos, be they on my computer or viewed online ( but far more often ones viewed online) will just...stop, at a certain point. It will not play past that point. I have to shift-reload or clear internet history to get it to "give it another go, so to speak" but if the video is longer than 2 or 3 minutes, there's a good 95% chance it will never make it to the end without finding some point to just give out on me on.
Granted, I haven't put any effort into fixing it since the last time I got frustrated by it and just gave up (where I updated drivers for my sound and video cards, got the latest versions of java and, well, everything I could possibly think of ((as well as things other people thought of, as I tried to internet search for people having the same problem as me, and followed the advice that helped them...still, no luck))
I'm really starting to get sick of this, especially as I want some fricking shows and the summer lull is kicking me in the ass.
Any suggestions?