Autodesk identified an issue when in a specific scenario, the Sheet Set Manager is using DWG files stored in a Windows 2008 R2 server with SMB V2 active.
As soon we open a Sheet Set from the server, Process Explorer shows that the process AdcomFolderWatch.dll uses until 50% CPU utilization, and the Network traffic goes up and stays at ~5 Mbps, even after closing all drawings in AutoCAD).
This issue only affects the systems having SMB Ver.2 active, like Windows 2008 Server R2.
The Autodesk development team has been informed. For the time being, the only way to avoid it is to enable SMB 1. See How to Disable SMB 2.0 on Windows Vista/2008
I will update this post as soon a fix will be available for this problem.
A fix has been released for this issue. AutoCAD and AutoCAD LT 2012 SP1 SMB V2 Hotfix