My Limited '18 is having all the above problems as well - so far I have seen -
1) Screen completely frozen and none of the buttons on the unit work
2) On call and the bluetooth connection drops
3) When using NAV, the whole system reboots
4) While I was listening FM, there was a loud screech and it crashed
I am taking the car to the dealer today and lets see what if they could do something about it. Sadly the issue is not happening now. But I have taken a video of issue 1) above. Fingers crossed.
@jannelle: Please keep us posted