Cannot read the next data row, but works after running ALTER sproc

Hi,

Every now and then SSRS report stops working and gives the common "Cannot read the next data row for the dataset..." error. If I look at what sproc is called from the report using SQL Profile, and run the sproc in Management Studio, it works fine. Only way to fix it is JUST to open that sproc in Modify window and do Execute. Reports are displayed in SharePoint 2010 web part.

Using SQL Server 2008 R2 (10.50.4000.0).

Where should I start looking for pointers to fix this issue? The error message is bit too common to be able to find anything related to specifically this issue.