Video File Has Pixelated Glitches and Green Flashed When scrubbing and exported.

I'm getting glitches when scrubbing through videos and exporting them. These videos are screen recordings on my Macbook Pro.

Examples:

Here a glitch appears behind Hillary's head

Original, No Glitch:
 

Exported Glitch:

The Same Glitch When Previewing/Scrubbing:

Another glitch I see is a green flash

This green flash appears whether previewing or after exported.

How do I get rid of these glitches?