Client resolution changes for a brief period of time when connecting with RDP, causing all my open windows to stack on top of each other

Question

Both machines have single large 4k displays. Similar hardware. Here is the .rdp file that I use to connect:

screen mode id:i:2
use multimon:i:0
desktopwidth:i:3840
desktopheight:i:2160
session bpp:i:32
winposstr:s:0,1,1120,133,3840,2130
compression:i:1
keyboardhook:i:2
audiocapturemode:i:0
videoplaybackmode:i:1
connection type:i:6
networkautodetect:i:0
bandwidthautodetect:i:1
displayconnectionbar:i:1
enableworkspacereconnect:i:0
disable wallpaper:i:0
allow font smoothing:i:1
allow desktop composition:i:1
disable full window drag:i:0
disable menu anims:i:0
disable themes:i:0
disable cursor setting:i:0
bitmapcachepersistenable:i:1
full address:s:XXXXXXXXXXXXXXXXXXXXXXXXXXXXX
audiomode:i:0
redirectprinters:i:0
redirectcomports:i:0
redirectsmartcards:i:1
redirectclipboard:i:1
redirectposdevices:i:0
autoreconnection enabled:i:1
authentication level:i:0
prompt for credentials:i:0
negotiate security layer:i:1
remoteapplicationmode:i:0
alternate shell:s:
shell working directory:s:
gatewayhostname:s:
gatewayusagemethod:i:4
gatewaycredentialssource:i:4
gatewayprofileusagemethod:i:0
promptcredentialonce:i:0
gatewaybrokeringtype:i:0
use redirection server name:i:0
rdgiskdcproxy:i:0
kdcproxyname:s:
drivestoredirect:s:

When I connect it drops for a second to something like 3200x1600 and moves all my open windows to the top left of the screen. Then returns to the correct resolution.

I recently changed from 3 1080p monitors on the machine that use to connect from to one 4k. The other machine (the one the connect to with RDP) had 2 1080p monitors and I replaced them after a while too with one 4k monitor.

Identical Windows 10 installations on both, with all updates installed.