[5.3] Elements in the UI flicker between different sprites

I recently switched from 5.1 to 5.3 for our project, and I got some issues with flickering elements in the UI. I've uploaded a gif of the problem:

http://gfycat.com/QueasyDeadlyLangur

As you can see, when I move the purple selection between the between the social buttons at the bottom, the logo at the top flickers with the FB or Twitter logo for one frame.
Also two button prompts in the bottom left corner (the Space bar and the Esc button) flicker with some other sprite.

My...

[5.3] Elements in the UI flicker between different sprites