Masks in Illustrator Creating Weird Shape

[Marisa5CC1]

I have a collage I made in Illustrator by masking, but when I zoom in/out/move around in Illustrator it shows weird glitchy shapes (they don't show up when it's exported). Does anyone knpow what is causing this and how I can fix it? I attached screenshots below, it's the part that almost looks like a shadow of a masked object.

[Kurt Gold]

What happens if you enable the CPU preview in the View menu (instead of GPU preview)?

[Marisa5CC1]

Unfortunately I tried that already! Nothing changed

[Kurt Gold]

That is actually good news because currently almost all weird preview issues are caused by the persistent malady called GPU Preview.

Can you share a sample Illustrator file with some instructions to reproduce the behaviour?

Also, which version of Illustrator are you using?