Seems my first post regarding this problem failed. In terms of analytical trouble shooting, the only thing that appears non functional now that was functional before is that no output occurs despite all input ( audio,midi,VST instruments) signals being active in Cubase software screens. Other system components are unchanged ( Cubase SX3, Platform -Windows XP-Professional, Powered monitors produce an output through the UR 28M unit ( Output level control on the unit works. As well, the direct monitoring tab in Cubase is 'greyed-out". Not certain if this should be active with this older version of cubase. I reinstalled Cubase SX3 and the drivers to the UR unit several times ( with uninstalls in between) follwing all directions that worked previously as well as making sure the Steinberg dongle and UR 'USB connections were in the same ports as during installation. The UR works perfectly on my laptop with Windows 7, but all of my software synths /plug-ins etc are versions for SX, thus, I need to get my desk top system working. Thanks for any advice from you are anyone else out there.