Emails for file changes, but none listed in logs

Loving this plugin. Thank you.

I just have one issue. I am getting emails from sub-sites saying that a file has changed. The email contains no details about the file.

When I go the the dashboard I am prompted to go to the logs to view the changed file, but no file is listed.

Should I be concerned, or is this a false positive?

http://wordpress.org/extend/plugins/better-wp-security/