I've created a GPO with QoS settings and I can confirm the PC is domain joined.
Name : Test
Owner : Group Policy (Machine)
NetworkProfile : Domain
Precedence : 0
JobObject :
URI : http://sub-domain.domain.com:443/
URIRecursive : True
DSCPValue : 12
I also have the registry modification
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\QoS
REG_DWORD "Do not use NLA" set to 1
And selected Applications' DSCP Marking Request to Allowed
One additional info is that, I'm not typing http://sub-domain.domain.com:443/ but https://sub-domain.domain.com/ in the GPO Editor. Don't know if that is expected.
If I look at the packet capture I don't get any change to DSCP. If I select "All aplications" I do get DSCP correct and working as expected.
