As per the Microsoft support site, in particular the "Nothing displays on the second screen" section, this adaptor requires HDCP support. This will require the adaptor to be connected to the HDMI 2 port on the Room 55, as this is the only port that supports displaying HDCP content.
Note - you will only be able to see the content locally, as it is HDCP content, it will not be able to be shared over a video conference.
Wayne
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