Martock
Warlord
Can't help you with the first one but second one I've had similar problems before and discovered my graphics card is to powerful for the game, so I lowered all settings down to medium except texture which I kept high and the problem has never returned, now this my not be applicable in your situation but can't hurt to give it a try and of course make sure to disable "GPU Texture Decode"
GPU Texture Decode has been disabled since day 1, but I'll try the other option of turning down the settings. If it helps, I'm all for it. Thanks for the suggestion.