I've recently rebuilt my dev machine with 2008 R2 Developer Edition and it's doing a strange thing. If I leave a SSMS query window open and inactive it gets disconnected. I'm connecting to (local) so I guess it's using the Shared Memory protocol. I've been using SQL Server since 2000 and I've never seen this behaviour before. Any ideas, please?
I havent seen your issue but I have had may strange problems with SSMS of 2008 R2; it is very buggy and if you havent applied recent cumulative update I suggest you do since it contains many fixes for the SSMS.