Sporadic Daily Backup Success Notifications (Backups do work however)

[pleskpanel]

While 30 domain-level scheduled daily backup tasks complete successfully each day, instead of receiving no notifications (the expected result since they all complete successfully), we receive between five and twenty emails that look like this:

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Backup task finished.

Task was created by with guid (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxxx)

Creation date is: 2013-Jul-23 23:02:02
Task status is: success

Dump full name is: (path to backup)
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This is on Plesk 11.0.9/CentOS with all MU's to date applied.

We only want to know when there are errors with scheduled backups (that seems like it should be the expected result).

What is causing these to be sent given that no manual backups are taking place?

 

[pleskpanel]

If we know that all backup tasks completed successfully, is it advisable to clear the contents of the /usr/local/psa/PMM/tasks/