Database Offline

Hello:

I have weird problem where around morning 1:35AM majority of my databases went OFFLINE in Windows Cluster 2008.

I only see this message in SQL error log "Setting database option OFFLINE to ON for database xxxxxxx event id 5084". beside that no other infos or error.

I checked cluster logs and see no errors or warning.

There was no failover or restart of SQL Server Services.

I checked default trace, error logs, event view logs etc  no luck.

there is no trace of user that might have took database offline nor I see any trigger that will take offline.

Any help or pointer is greatly appreciated.

Thanking in advance.

Thanks