Can't watch live TV with ATI HD4870

I’ve got a Nova-t dvb(t) TV card, and an ATI Powercolor HD4870 GC. I’ve installed the 3D drivers for it via the repository, every thing seems ok bar the fact that I can’t watch TV live, If I record with kaffeine and playback it’s fine, but watching it live displays either thick diagonal lines, I can’t see anything of the picture, or the top half of the picture is ok, but the bottom is faded out. Very often after a couple of seconds of this X crashes and I’m returned to the X console login.
I’m absolutely clueless how to fix this, there is a wealth of settings in sax2, don’t know if any of those would help. I would really appreciate it if someone could help me out.

It seems to be a problem with the video driver ‘xv’, when I change the xine engine in kaffeine from xv to xshn I don’t have this problem, though the picture flashes and stutters when on fullscreen. I can’t use any other drivers listed in the kaffeine/xine video options.