Encoding artifacts: pitch black turns into flickering?

Hello, What should I do to fix visual artifacts like these: The map borders are of black color. But if you watch closely at the icons in the top right of the screen, you can see flickering pixels there as well. Or could it be not the color, but areas of completely flat color instead? More information: I'm using Windows 8. This video was recorded with HyperCam, using Microsoft Video 1 codec (codec-wise, the options were limited). It was then trimmed in VirtualDub, but this shouldn't affect the video much since it was exported with "Direct stream copy". At this point, the video is still artifact-free. After x264 (using Staxrip GUI), the artifacts show up. Staxrip settings: Code:

What happens if you use another GUI ? e.g ripbot, handbrake etc... What decoder was used in staxrip? Maybe posting the staxrip log will help provide clues

Thanks for the reply, Ripbot seems to work, encoding the video without artifacts. I'll attach the log files from post GUIs.