1. Update your Windows per
https://obsproject.com/blog/five-simple-tips-for-new-streamers
2. Run OBS as Admin
3. Having the YUV Color range set to "Full" will cause playback issues in certain browsers and on various video platforms. Shadows, highlights and color will look off. In OBS, go to "Settings -> Advanced" and set "YUV Color Range" back to "Partial".
4. Display and Game Capture Sources interfere with each other. Never put them in the same scene
5. Multiple Game Capture sources are usually not needed, and can sometimes interfere with each other. You can use the same Game Capture for all your games! If you change games often, try out the hotkey mode, which lets you press a key to select your active game. If you play games in fullscreen, use 'Capture any fullscreen application' mode.
6. Your GPU is maxed out and OBS can't render scenes fast enough. Running a game without vertical sync or a frame rate limiter will frequently cause performance issues with OBS because your GPU will be maxed out. OBS requires a little GPU to render your scene.
Enable Vsync or set a reasonable frame rate limit that your GPU can handle without hitting 100% usage.
If that's not enough you may also need to turn down some of the video quality options in the game. If you are experiencing issues in general while using OBS, your GPU may be overloaded for the settings you are trying to use.
Please check our guide for ideas why this may be happening, and steps you can take to correct it at
https://obsproject.com/wiki/GPU-overload-issues
7. Your stream encoder is set to a video bitrate that is too low. This will lower picture quality especially in high motion scenes like fast paced games. Use the Auto-Config Wizard to adjust your settings to the optimum for your situation. It can be accessed from the Tools menu in OBS, and then just follow the on-screen directions.
If still having issues after making those changes, run log through
Log Analyzer or post new log.