Glithy/Multi-coloured lines in video after export

Screenshots of issues added to post.

After exporting media from Rush, the playback is full of glitchy sections that appear with multicoloured lines randomly placed throughout the length of the clip. Tried both VLC media player, and QuickTime media player.

Playback within Rush itself is jumpy and not at all smooth, but features none of the lines or glitches viewable in the above mentioned media players.

I also have an issue where using two or more clips of identical size on top of each other in the same position in the additional timelines causes the clip in the second timeline to become completely distorted, 

Using a 2013 MacBook Air wuth the most recent version of Rush

Processor: 1.3 GHz Intel Core i5

Memory: 4 GB 1600 MHz DDR3

Graphics: Intel HD Graphics 5000 1536 MB

Rush export settings:

Exported at both 1080p and 720p with the same problems at both speeds.

Frame rate 30

Video Quality: High

Would really appreciate any and all help, thank you so much.

Daniel