When using output preview, the document not only flickers, but it also zooms in automatically.

Upon opening the Output Preview tool, the document begins to flicker. When I turn off a separation color, the document auto zooms in really close. These problems only started on my MAC maybe a couple weeks ago. This is the OS version I am using:

This is an example of the document when first opened in Acrobat DC Pro:

 This is an example of that same doccument when I uncheck a color in output preview (doesn't matter what color). This will continue whether turn on or off colors:

Any suggestions on a solution to these issues? Would appreciate any input on troubleshooting this. Thanks!