RDP 10 4:4:4 Mode Issue

Hi Everyone,

I'm trying to evaluate the new RDP 10 4:4:4 mode.  I've setup the Win10 1607 virtual desktop on a 2016 TP5 host, and set all of the GPO settings.  If I connect to the 2016 Virtual Host, I get the following:

Event ID 162:  The client supports version 0xA0200 of the RDP graphics protocol, client mode: 2, AVC available: 1, Initial profile: 2048. Server:myservername

Event ID 162:  The client supports version 0xA0002 of the RDP graphics protocol, client mode: 0, AVC available: 1, Initial profile: 2048. Server: servername

Event ID 170:  AVC hardware encoder enabled: 1, encoder name is NVIDIA H.264 Encoder MFT. Server:servername

When I connect from the same client (Windows 10 1511) to the virtual desktop, I get this:

Event ID 162:  The client supports version 0xA0002 of the RDP graphics protocol, client mode: 2, AVC available: 1, Initial profile: 8. Server:servername

So, it never kicks in the 4:4:4 mode.

Can someone tell me why I'm getting different results from the same client?

Thanks,

Kevin