XPS 13 9310 slow boot on DELL splash screen when connected to USB-C monitor

I have an XPS 13 9310 connected via USB-C to a Samsung S60UA series monitor.  I'm using the USB-C port on the left w/ the Thunderbolt icon and it's providing power via the same connection as well (I'm not using the Dell power supply).  When I boot the system with the monitor's USB-C connection, the system will hang for a bit on the DELL splash screen.  I estimate that it'll sit there for at least 30 sec before the Windows login screen appears.  However, if I disconnect from the monitor and boot, there's no such hang-up.

I've been through several BIOS and driver updates and the problem still persists.  I also couldn't tell if there's a setting in the BIOS that I should check/uncheck that would help this, though not all of the setting descriptions are clear to me.

Does anyone have any suggestions on what I can do or why this is happening?  I'd prefer not to keep plugging/unplugging the USB-C connection to the monitor every time I need to reboot.

Thanks!