Ive only had my forum running a few days but members who have clicked to not receive email for topic notifications in their profile prefs are still getting them. Is there anything I can do to stop this? I usually want them but turned them to see what happened, lasted an hour or so but now they are back even though my prefs are the same....

Just go into profile>Topic being watched tab

Remove the topics from there.
Save

Yep that works until the next time someone posts.... dont want members having to go to their preferences every time they post in order to stop getting emails. Why does the main option not work?

Its not needed to do that every time. There is no option to disable this for all users.

Go to Profile // Preferences // look for email me for topics being watched // No // Save

Thats already been done MrMario but they are still coming through....

Does it happen with new threads?

I've asked people to tell me if its all threads they've posted on or topics they have started, seems to be a mix.

Well, just doing it via Profile>topics being watched
Removing all the threads.

Then doing as MrMario suggested to sort the settings for you.

You should guide your members to do this. Then give us a feedback.