Bandwidth Overages - $70

I've just been billed by our datacenter for using up over 1.2 TB in bandwidth last month.
I find it absurd because I seriously do not believe that the hosted sites on the server have enough capacity to do that much damage.

But before I start complaining there, I'd like to know how I can run reports in order to find out what the biggest bw usages are on the server.

Any ideas on how to run such a report?
Thanks.


EDIT:
I've just run reports on WHM and total bandwidth usages have been listed as 482.34 Gig

So the extra bw usage is non-http related. Where do I start to figure out what is causing this?

 

 

 

 

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