Run a server side profiler trace since I have sleeping spids appearing occasionally on the server. noticed some SqlTransaction events where DatabaseName column shows null . Majority of the SQLTransaction events have the Database name populated but just a few have them null. I tend to see a correlation between them and blocking since these spids keep a transaction open and this creates blocking on another transactions.
Looks strange to me why the database name would not be populated. the LoginName has privileges on one user database on the server.