Hi Mark,
Could you please visit
http://www.4x4response.info/profile.php?do=editoptions and confirm "Default Thread Subscription Mode" is set to 'instant notification (sorry if you've already checked this).
Then go to
http://www.4x4response.info/subscrip...ewsubscription and confirm the threads you are subscribed to say 'instant' notification on the far right column. If you previously had another setting and have only just changed it threads that you were previously subscribed to may be on the old setting, you have to tick them then update them from the drop down below.
Please let me know how you get on with the above and we can go from there.
Cheers
Patrick