Thank you – I did read that before posting. I’m only using two other plugins aside from Contact Form 7, Contact to DB and Captcha. I’ve tried deactivating them and switching to a different theme (I’m using Enfold) but still having the same problems.
I’m running the exact same set up on other websites (theme & plugins) but with Contact Form 4.2 and they are working fine. I very reluctant to update the plugin on the sites in case the same issue occurs.