An error occurred while trying to access the audit log

Hi I have run Set-Mailbox ian.shapton -AuditOwner Update, Move, MoveToDeletedItems, SoftDelete, HardDelete

I then created and deleted an email and ran Search-MailboxAuditLog -Identity "ian shapton" -LogonTypes Owner -StartDate "12/21/2014 12:00" -EndDate "12/21/2014 13:00" -ShowDetails

I see An error occurred while trying to access the audit log. For more details, see the inner exception.
    + CategoryInfo          : NotSpecified: (:) [Search-MailboxAuditLog], AuditLogException
    + FullyQualifiedErrorId : [Server=Mailbox01,RequestId=07f17915-f25d-4fd5-b23e-f07a2482f4a4,TimeStamp=21/12/2014 16:45:39] [FailureCategory=Cmdlet-AuditLogException] 255D6156,Microsoft.Exchange.Management.SystemConfigurationTasks.SearchMailboxAuditLog

MSExchange CmdletLogs shows Microsoft.Exchange.Data.ApplicationLogic.AuditLogServiceException: The Exchange Web Service returned an error while trying to access the audit log. Reason: 'Error','ErrorTimeoutExpired','The search operation could not be completed within the allotted time limit. Please try to narrow down your scope to reduce the result set.'.

I am a Recipient Admin and Org Admin and can search other mailboxes using -LogonTypes Delegate

Any idea what I am missing here?

shapi