Have you look at this:

http://blogs.msdn.com/b/dipanb/archive/2010/06/09/sql-server-query-performance-when-running-query-from-a-windows-2008-server.aspx

We are seeing the same thing, but are in the early stages of the investigation.

Erik

If you have a report with parameters with default values that comes from a query and setup the report to refresh every 2 minutes, will it update the default values...