The dashboard map is actually being "drawn" by Google Maps running on the android infotainment computer (IHU). The car's real-time OS (that runs most of the dashboard) provides a shared graphics buffer that it allows the IHU to write into. So it could be an IHU problem, a memory/buffer issue on the dashboard system, or communication issues between the two.
My apologies, up front, for going off on this thread but, here goes... Believe it or not, I bought the car in June and had the IHU replaced in late July. The map maintained it's quirks, after the IHU replacement, but started this new fireworks show after the July Factory Update, which was downloaded at the dealer. Now, my radio hasn't been working for the last few days. Google assistant is also coming to life on it's own, without any prompting. My car is possessed, I tell you. LOL To add to this list, I jumped into my car one morning, to pull something from the glove box. No key fob in hand. The car came to life, where the car actually turned on, as if the fob was nearby. I didn't think that the car could do that but, what makes it more complicated, the car remained "on" after I shut the door. An hour later, as I walked up to my car to drive off to work, I noticed that the car was still "on". The doors were all closed properly. When I got in, I noticed that I lost 4% battery power in that hour that I was gone. I've read another Forum note that someone left for a road trip for a few days, in a different car, only to come back to a drained P8 main battery. I'm betting that they jumped into the car, before they left in their other vehicle, and the seat trigger kepted the car running; draining their battery. Glad that I didn't drain mine, completely! To go on, my Harmon Kardon stereo is garbage, when it plays. Only getting sound in the front, where the rear speakers play at about 75% lower volume and there is no Fade feature, nor left/right balance, nor Equalizer. The 3 loaner cars I've driven, all XC40 T6's, all had standard radios that tuned wonderfully. So disappointing! Lastly, my brakes stick after they get wet and dry out overnight, and there is clacking noise, in the rear bottom of the car, that "pops" on every left or right turn. The dealer needs my car to camp out at the service department for a few more days to remove all the wheels and check out what's going on, with the brakes and everything else. After owning the car for 3 months, and driven almost 9,000 miles, I can honestly say that this has been the worst car purchase ever made! Too bad that I really love the car, otherwise. Hard to pull the Lemon Law card but I'm running out of patience with "Ingrid".