Denominus

Sometimes I can go for hours without it happening. Other times my UI bugs out every few minutes and the only fix is to restart DCS. Also a 5700XT user.

Old post, but this happens to me at random as well. Normally halfway through a long mission. It's not just the map, other parts of the UI break. Buttons completely lose their background and border. For instance, going back to the main menu after this happens, the module buttons at the bottom of the screen lose all their icons and just become text.

I had exactly the same problem with a Radeon 5700XT. SSAO causes black square flickering artifacts in the cockpit, I was able to resolve it by finding this thread and disabling SSAO.