I have this problem to with an old radeon hd4000 and kernel driver, for me watching something with hdmi connected means instant problems, it comes unresponsive but keeps playing until I kill it.

Just watching movies will lock it up a bit into whatever I'm watching and I may have to resort to holding down the power button, but this is happening as well when using flash but not html like on youtube.

I need to try downgrade vlc it used to be perfect.

[edit]
Now that I'm thinking about it I believe this happened in xine to, and it was better with kernels prior to 3.18.9, but this laptop is rather dated and I am about to retire it so I didn't bother

So I decided to work on this some more tonight and I have 100 narrowed it down to VDPAU. The only thing I can find on the net so far that seems related to my problem is here.

http://askubuntu.com/questions/58446...vers-installed

I rebuilt Alien Bob's package and just disabled the vdpau flag. So far 2.2.1 is now working 100%. Still searching around to see if there is fix for vdpau/vlc.

I found some clues after digging around various forums. I just rebuilt VLC again but I upgraded Eric's 2.2.1 build with vdpau-1.1 and libva-1.5.1. So far this seems to have fixed the problem. However I am going to run this for a day or two before I mark this thread as solved.

Well guys just a quick update. I thought I had this problem solved but I am still getting crashes. After looking through the logs and console it looks specific to the vdpau_chroma, Still not sure if this is a Nvidia, libva, vdpau error. Still searching around for a fix, but for now I just disabled vdpau in the build all together. Good enough for now.