Don't know if its related to the update then downgrade but I've had this issue since I tried to install that update and then had to downgrade:
My fuel units were set to mph since I had the car. I have had the head unit installed for 2 months now and there have been no issues with this, but yesterday for some reason my speedometer switched to kmh and I am unable to switch it back.
In the "vehicle settings" menu, under fuel unit settings, there is no option to set it to mph, only these two:
