One thing I’m trying now is uninstalling Tunnelbear (a VPN program). This thread https://www.reddit.com/r/Windows10/comments/4o0v01/windows_firewall_keeps_asking_for_permission_to/ seems to point to Tunnelbear as the problem, and when I contacted Tunnelbear’s support, they acknowledged that they are investigating the issue.
Since uninstalling Tunnelbear, I haven’t had any problems – but it’s too early to tell if it was the culprit.
Would you have Tunnelbear installed @Joe?