Following endless trouble shooting and swapping cables I still cant get the CSV-5400 to work properly. It wont even support 2 screens on HDMI at all. When it was working with 1 HDMI and 1 DVI and I swapped the MDP2DP6IN 6 inch input cable to a MDP2DPMF3 that was 3 ft long and specified to work at 21.6 GBbps it would not sync to the 2 screens again. I confirm that I have pressed the scan button appropriately. All these troubles only started on 18th Jan ie after the graphics card was updated to v10.18.14.4029 and I am now wondering if that is the root cause. even though it seems ok on your surface 2.