I have had this ongoing issue and as many times as I look in settings I can not seem to figure out what to change. When someone posts on the discussion board, everyone who is subscribed gets an email notification that there is a new post - the issue is when the email notification comes through. People do not receive the email notification until several hours later.
This is the same thing with the teacher receiving email notifications for students completing their assignments. Also, when teachers comment/give feedback, the students do not receive a notification until later.
Everything shows up in Moodle at the time it was posted and the email notifications do come through, I am looking to fix it so that the email comes through right when the item is posted. Thanks!