Re: Since TODAY i got black screen!
I am the author of the program. Your logs don't actually report any problems, so based upon that fact and what I've heard in the past, it seems like something is interfering with game capture if you want my guess based upon experience. Overlay applications such as teamspeak/mumble overlays, graphics modification applications such as sweetfx, game-specific graphics mods, or other capture applications such as fraps/etc. Not entirely sure what to suggest because of the lack of actual errors in the log file.
You could always just try using window capture and run the game in a borderless/windowed mode if it still continues to have a problem, but as a general rule of thumb, if you suddenly start getting a problem without changing OBS versions or settings, then it most likely means something else changed on the computer, whether you might want to hear that or not, whether you might be aware of it or not.