Weird issues with only some php pages

[Shill360]

I am having a very strange issue that has only happened since 2 days ago. No pages have been modified and no templates changed. Nothing installed.

The issue is that some php pages are just not being displayed, there is no error message however on the browser, just a white page saying done. My host says there are no error messages on the apache server.

I have tried changing templates to see if thats the issue but it isnt, the same thing happens on the default vbulletin template. I have also tried replacing the files with original ones but to no avail.

The pages in question are as follows

/forums/online.php
/forums/member.php?u=xx
/forums/blog.php (mod)
/forums/staff.php (mod)

All other php pages work correctly and load fine, both standard vbulletin and addons.

Anybody else ever had this problem, and if so how did you fix it.

I am currently on version 3.7.2

An example of this page is here - http://www.onlinearsenal.com/forums/staff.php permissions are set to allow this page viewable to everyone and anyone.