How to stop Activity Log from logging Google Calendar every hour

I have All-in-One Event Calendar installed and it checks and updates Google Calendar every hour. But Activity Log treats every single check (143 items at the moment) as a NEW event (Post – label: Events – Updated). There has been NO change to any of these items, but Activity Log doesn’t seem to realize this. I can’t monitor changes to regular Posts if I remove “Posts” from the list of things Activity Log monitors. (We’ve been suffering from link injection-type hacking – it’s been fascinating to see the number of login attempts now that we’ve changed all the user passwords!)

If there is some way I can filter OUT these non-existent updates, could you please let me know? Even if I could filter out the changes by IP number, since the requests come from the web server, that would work. But I don’t know how to do it.