Ah, with a custom Enterprise image on Surface, it is hard to say what "current" might be. the latest driver for Marvell, the new driver model ending in .47, was installed for folks with the regular retail image when they installed the update to TH2 1511.
The drivers at https://www.microsoft.com/en-us/download/details.aspx?id=38826 are still from 10/26, i.e., the OLD drivers.
You may need to open a support case to get these newer drivers if you've upgrade to 1511 and don't have the newest drivers.