When a user wants to subscribe to a newsletter list in MailChimp they get 3 opt-in emails.
I have tested it with diffetent emailaddresss, disabling/enabling the add-on.
MailChimp sends 3 ( 1 every second) e-mails which have been sent from mail2.mcsignup.com.
Looks like the form submission is sent 3 times to MailChimp..
Any help would be appreciated.