My MMI control unit stopped working in July. My local Audi service center performed a hard reboot which temporarily solved the issue. Then in October, the MMI navigation features stopped working. My Audi service center installed a new control unit. This week, that replacement control unit stopped providing voice guidance (turn-by-turn instructions). I now have a second control unit on order after just 10 months/10,100 miles. It’s a bit alarming since the unit costs $2,500-$2,800 – not something I’d want to pay for out of pocket if this were to happen again after the warranty period expired. Has anyone else had this issue?