I have managed to sort the issue out. It is however not a quick fix.
The answer is to do a full recovery device reset and re-install then download the latest Surface studio 2 Firmware and drivers .msi package putting in a totally fresh OS and driver build.
After completing this .. 1 - 2 hours all told the Surface Studio 2 feels very quick and quiet, just like it should have been when it arrived !!!
Honestly it feels like a completely different machine, everything is so much more stable and snappy. I was having many error, shutdowns and crashes in sleep mode, netflix closing down randomly. None of the above is happening any more, even the Surface bluetooth
headphones connect and disconnect and work better.
The gpu 3D and video decode load using 4k video say on Youtube is 1/3 of what was being used before. I have no idea what the factory install did, but QA really need to step thier game up.