I tend to get this bug from time to time with no apparent reason, sometimes it happens in editor as well. Could start of the game, of 40 minutes into the game. Everything but UI turns into "noise". I tried pressing F5 - it never helps. One time, clicking chronocam and going back solved this problem, I tried this trick the other time, it didn't help. This last time I was playing alliance FFA, I was left alone against 3 allied armies, and I was doing pretty well, when this stuff happened. Knowing that there is no option to go to menu now (your comm would explode), I proceeded to play... like this. Because odds of me winning were pretty high. So the only thing I could use was strategic icons. After 10 minutes I realized that I could alt+f4 and reconnect. I did it and everything was back to normal. However, falling out of the match for ~5 minutes and losing all your control groups and camera anchors is not what you usually want to do.
There still isn't a way to reproduce this error, so it is very hard to track in the code for Uber to fix :3