[ahgee2]

Check dmesg for further info - I think it's a driver bug. Can you try another card?

I spent a few hours trying older versions of Openelec and don't think I can add anything beyond what zag summarised in post 2613. I have r17733 (19 February) rock solid stable, r17811 (25 February) blocking/pixelating and eventually freezing with live TV, and all subsequent betas not working like r17811. I cannot find any archived nightly builds between 19 and 25 February to help narrow the search, but am happy to try others if anyone wants to point me in the right direction. The kernel bumped from 3.13.3 to 3.13.5 between r17733 and r17811, so could be driver issues. I didn't see anything in dmesg though. I was looking at the xbmg.log file in real time, and didn't see anything when there was blocking/pixelation, though there were some errors when the stream eventually froze. Log files are here:

r17811 broken:
http://xbmclogs.com/show.php?id=189867

r17733 working:
http://xbmclogs.com/show.php?id=189870

Please don't hesitate to ask if there's anything further I can do to help, I am reasonably Linux literate .....