XPS 13 (9350) won't remember main display on wake

Hello,

I have an XPS 13 9350 and a U2414H monitor connected with the Dell USB-C to HDMI connector.  Everything basically works, and I have set the external monitor to be the main display.  However, when the computer goes into sleep/hibernate mode (or is turned off), it will forget that my main display is the external monitor, and I have to set it again every time it wakes up.  Is there any solution to this?  

Thanks!